Here is the thing,
They want the best, and sometimes they relate the school you come from with the quality of education you have. The better the quality of education you have, the easier and cheaper it is for companies to train you. So in essence, if youre just looking at schools, the top universities win talaga on that regard. However, if they see you have amazing experience related to the job, you also win regardless of what school you come from.
Essentially, it comes down to how easy it is to train you, and people who came from top universities are often those people. Kasi cheaper for them and they love cheaper costs.