[Edit: I mean why do students choose the way they do?]
Brand in the CS sense is still huge. For some reason students just seem to love working at companies that are famous in the tech circle.
Perks also have a disproportionate impact on students who are used to college life and also don't quite internalize costs. We'll take a salary cut to have silly fringe benefits like laundry.
Finally, I think two delusions play a huge role: (1) That big companies offer more "interesting" work, which I think is empirically false. You're far more likely to be fixing bugs in old code in one of these large/famous companies than inventing new algorithms. (2) That "interesting" work is desirable. I honestly don't understand why students especially think they're above working on a CRUD app. Sure, it sounds "cool" to be dealing with things at Google scale, but I'd personally rather have a tangible impact on a company's core product.
Personally, I don't buy into any of the hype and turn away all recruiters from brand name companies. I can make twice as much, and work reasonable hours, in building "uninteresting" code for random startups...
Myself included, it is easy to forget you have a lot of work to do at these places. I've heard these places described as "adult Disney land ", "just, better than the east coast " and "way better than Google " by recruiters.