Of course there's a moral issue, but it goes far wider than Brixton. That said, people here use Brixton as the example because we live here, we see the poverty, and we see the effect that expensive clubs, bars and restaurants are having, especially as some, perhaps a majority of those outlets, repatriate their profits outside the area. That might not bother the majority of posters, or even more than a tiny minority of Brixton residents, but it bothers me because I've been watching this happen in different parts of south London for over 40 years now, and I'm fairly well-acquainted with how the story plays out.
And who is it judging what comprises sneering, and who is sneering, teuchter? You who won't judge how people spend their money, but are happy to judge posters whose worldview and morality differ from yours?
In my own case, I don't "eat out". Most restaurants aren't disability-friendly in terms of accessibility yet, and likely won't be until accessibility is mandatory - even then, it'll only apply to new-build.
I'm not sure people are objecting to "frivolous spending when eating out". It appears to me that the objection is to the price per se, and perhaps to the knock-on effect that higher prices can have on other outlets. We've already seen "local" restaurants closing over the last few years because of rent/lease cost issues. I certainly worry that rentiers are encouraged by higher prices in "entertainment"-based outlets such as club, pubs and restaurants, and that this feeds an already-existing problem for locals.
I don't object to people spending their money as they wish.
I find spending £20 on a "faux Berlin Brunch experience" sad. I find it sad for 2 reasons:
1) As you've already noted, it's likely to be inauthentic.
2) You're unlikely to pay the Euro equivalent of £20 on brunch in Berlin even at a decent quality restaurant, rather than a cafe.
A more affluent population is moving into Brixton. This means that businesses and landlords have a wealthier market to cater for. This has the consequence that some of those less wealthy who have been living here for some time are priced out of housing and/or find that their shopping and entertainment options narrow. I think we can agree that this is happening, and that these are not consequences we like to see.
So, what to do about it? That question has to involve considering the causes rather than just the symptoms. It's caused of course by things taking effect on a much larger scale than Brixton and these are indeed much discussed on here, on other threads at least. There's lots of stuff that could happen to ameliorate the situation. Rent caps. Tenancy law reform. More social housing. Protecting existing social housing. Making developers stick to their affordable housing quotas. Planning policy intervening, at a local and national level. No doubt you could much more to this list.
These things get a mention but so often they seem to be drowned out, on this thread in particular, by a focus on the symptoms. Discussion at length of what type of people are spending what amounts of money where and on what. The way they are dressed. The way they speak. That the events they are attending are not "authentic". That the food isn't served on plates. That the cocktails have silly names. How much they are paying for something that they could have bought in Iceland for 50p.
Can't deny that I sometimes indulge in making fun of that stuff too. But it seems to me that relatively harmless piss-taking gets mixed up on here with the anger about the wider changes in Brixton and then it's not just having a bit of a laugh about what other people get up to; it's a kind of attack/judgementalism disguised as something more benign. An attack on a vaguely defined group of people. Poshos out, yuppies out, hipsters out. You don't need to give me a lecture on why it's not the same thing as saying "no blacks or Irish". I get that and I think most readers of this thread do too. The point is not whether it's "as bad" as that but that it's wrongheaded for similar reasons. Lazy thinking that doesn't help do anything about the underlying issues. I would argue counterproductive, even.
You say you "don't object to people spending their money as they wish". If you say so, but I see a lot of posts on this thread which as far as I can see revolve around just that. There definitely seem to be objections to people spending a certain amount on certain things. Why otherwise these cost comparisons of restaurant meal vs weekly shopping bill. Or tasting-menu tours vs volunteer local history walking tours. Or popup dinner vs 2 pints in the Albert.
On the other hand you say the objection is to the price "per se". So there is an objection to certain things costing more than a certain amount. Ok. So this is presumably an objection to the businesses rather than the customers. But what exactly is the objection to and what is supposed to happen differently? Should the businesses set their prices lower than what they can get away with? At some unspecified discount to whatever the going rate is? Does whether or not they live locally affect how they should set their prices? Should they reduce their prices even if their rent is going up? You talk about the "knock-on effect that higher prices can have on other outlets" as if those higher prices aren't already the knock-on effect of something else. It's just an "objection" to symptoms rather than causes again, is it not?
And like the "objections" to the spending of money in certain ways, the "objections" to businesses seem so often to turning into an attack on a person or a percieved person or type of person. Suddenly the size of their kitchen seems to be part of the objection and in effect we are back to judging them on "spending their money as they wish". And why do small scale operations like the market tour get such a disproportionate amount of flak compared to, say, any number of nightclubs which must turn over sums that are orders of magnitude greater? It looks suspiciously like these objections aren't just the result of concern about the overall story that's playing out but are somewhat selective. Maybe some have a tendency to turn a blind eye to those establishments they themselves like to attend, despite them being every bit tied up in the "overall story"?
By the way, I haven't actually said that I don't "judge" anyone. I am liable to come to certain conclusions about people according to their apparent wealth. Of course it's not totally irrelevant; people's wealth can indicate how they are likely to percieve the world and what their vested interests might be. But when people are making comment on the wealth and spending choices of others (either individuals or perceived groups) it's a bit rich to act all indignant when it's pointed out that maybe they themselves are fairly privileged relative to the benchmark they are using (ie Brixton's poorest) to make their pronouncements. Because ultimately the only argument being made is a simplictic one that something is expensive relative to something else.