Actually, what I fail to comprehend is why you persist with this quite frankly ridiculous argument.It's facts. I've provided numerous links to back up everything I've said and you have no answer to it. You, on the other hand just make sweeping assumptions about 'all tourists having a travel card' and that walking 0.3 miles - as verified by google maps and walkit.com - might be less preferable than using the assistance on hand by TFL staff and the extra support offered by taking the tube.
Your failure to comprehend why anyone would do this, or why a tourist may also unwittingly do this further demonstrates your ineptitude to look at life from any other perspective than your own fantasy revenue collection officer world.
And of course all tourists would have a Travelcard; why wouldn't they? Have you ever dealt with a tourist? The answer is "no" isn't it. On the Trip Advisor London forum every other question is asking about Oyster or Travelcards.
TBH it seems like you think that tourists and "disabled" people are as thick as two short planks. What was that about "living in fantasy world".........?
And Walkit.com told me 0.2 miles, but whatever it's definitely not the "3rd of a mile" you keep claiming. I also think you are lying about having walked it, because you don't seem to have any idea of the actual distance in reality, nor how short it is.