I am a Rice grad student and frequent Valhalla-goer. In three years I have never once encountered a rude bartender there. But I don't confuse it with a normal bar. FYI if you ask for a Bud Lite, you might be taunted. Drink better beer.
Yes, parking absolutely sucks. It is largely patronized by Rice grads, alums, staff members, and groups of joggers. If you aren't in one of those groups, there isn't a compelling reason to go. It's an on-campus pub, people. Also, I am a woman. Women go to Valhalla.
And I agree that UH has much better food. Frenchy's is the best fried chicken in Houston. Rice is a food wasteland, which is why I am often at Valhalla's for lunch buying Les Givrals bahn mi.