Unless appearances are some better indicator of a person's quality than wealth neither is more or less shallow than the other, but one is judged to be moreso. If that's not sexism nothing is.
This is also the difference between gold-diggers and normal women: gold-diggers are conscious of the fact that they're trying to score with rich men.
Would they? Maybe I've just been hanging out with too many women (in a non-sexual context), but they complain about guys that talk to the obviously-prettier girl at the bar all the time. Meanwhile, talking to the more successful-looking of two guys is pretty normal, as long as you aren't blatant about it (eg. asking how much they make).
I think it's more that girls will judge guys for going solely for attractive girls, and guys will judge girls for going for richer guys. Both sexes are shallow, both sexes complain about shallowness in the opposite sex, and most people of both sexes will recognize that basically everyone is shallow - in private. But public discourse tends to feature more males, so we hear more about how golddiggers are evil than about how babewatchers are evil. Either that, or it's just because we're male and girls tend not to share their real opinions for fear of offending us.
Similarly, men are statistically more likely to exhibit violent behavior (and there is an evolutionary basis for this). Therefore, condemning violence is sexism, since the condemnation has a disparate impact on men? Um, no.
One may or may not be a better indicter of long term compatibility.