How many times have Celtic had to close the safe standing area since it opened? Quite a few isn't it?
Also it is fan mentality. I've seen it many times at England and Brighton away games, I saw it at the Euros with England fans (proper ones) tailgating into the lower tier to be with their mates...
I do think this is set up to fail - especially without strong stewarding in place.
Celtic have already seen issues with 'The Green Brigade' taking over the safe standing areas and throwing out those with tickets there so they can be together. Coupled with other drink issues etc you can see...