I think some people are fairly horrible, self-centred bar stewards. They probably don't have a very nice life and want to exert what little power they have on whoever they feel they can exercise it on (or they think they can exercise it on). They probably can't get pleasures in life due to their horrible attitude, either, which probably adds to their frustration and they take it out on others. I could say more but I shall stop or I may end up getting banned for being naughty!

I'm still trying to figure out what completes the T------ though. Do give me a clue, because I'm struggling here. I came close with one option but it only has 6 letters.