Maybe it had something to do with the place Pavement was in their lives?
Pavement isn't high on my list of things to listen to, but there is always the chance they were important when the artists were developing. I would easily put pre-warning green day as one of my influences, but I've found people who are in their mid-teens now and consider that stuff just kind of boring and bland.
Maybe it was because they pioneered the genre?
I'm not familiar with their place in 'indie' history, but they might have invented a lot of the style that is used by modern 'indie' bands. If you listen to Hendrix and compare him to some modern technical masters, he's easily been surpassed in skill. That doesn't change the fact that he was on the forefront of modern music, that doesn't change the fact that he was influential to all those guitarists that are 'better' than him.
Maybe I'm a cynic and it's easy for the pretentious to like pavement?
Pavement has a bunch of good, enjoyable rock songs, with the odd 'artsy' hooks. You've probably noticed a bit of dissonance or odd parts of the song that don't seem to flow well. At first, this will throw you off, but it does grow on you and after a few listens through, they get a lot better. But this is enough to dissuade the casual 'mainstream' ear, so Pavement becomes a great rock band that those 'pop fans' will never really get interested in.
For the record, I'm very tongue-in-cheek when I'm referring to groups/styles/genre. I don't think any of that stuff really exist, but that's irrelevant to Pavement, and it let's me simplify things.
EDIT: Shoot, I just re-listened to 'Brighten the Corners' for the first time in a year or more. I'm totally in love with pavement now.