Being able to avoid 4 people quietly giving out a few leaflets (that most of the people demanding the removal of the 4 people there admitted they hadn't read) hardly strikes me as an act of violence that threatens a space being safe, especially in a gathering of anarchist revolutionaries. If that's something you can't cope with how did you even get through Manchester to even get to the Bookfair, or leave your house every day?
And I'm sure there are accessible venues in Manchester, but I think it'd nice to give the Bookfair collective the benefit of the doubt that there were really good reasons (cost, availability on certain dates, etc. etc.) why they couldn't use them... or we could just do what seems to be in vogue at the moment when dealing with comrades and just publicly denounce them as fucking disabalist scum that need driving away from politics for the safety of everyone.