Anywhere that you cannot be yourself or feel you have to "hold it in" on MDMA is going to be uncomfortable, I find drunk people to be pretty crass when I'm sober, if I'm rolling even more so. I know not everyone has the same opportunity, but I strictly only roll at large music festivals, preferably camping out in nature. Some people like rolling in clubs, I have a couple times but the environment feels too "exposed" and drunk people galore, feels a bit tacky.
I guess it depends on the bar, and some bars are more like clubs, but I could totally see a "pub" throwing someone out for being high as shit on MDMA lol, its quite obvious.