I think it's not whether Google is a desirable place to work, it's whether it's more desirable a place than other places that do not require an application fee.

I think it's not whether Google is a desirable place to work, it's whether it's more desirable a place than other places that do not require an application fee. Or, to be more pedantic about it, whether the marginal value of applying to Google is worth the cost. My hypothesis is that for most good candidates, working at Google is not highly differentiated vs, say, Facebook, Apple, hot startup, etc. It might be for some subset of applicants (potentially those with big interest in search, or people who live right next to a Google office). Of course, those people would have applied anyway. My instinct is that many more desirable applicants would just think, "I'll just apply to Facebook and Apple instead and see what happens." Pulling out your credit card is just such a big conversion barrier that I can't see this being a good idea.