Hi temuchin43 - welcome to GMAT Club!
The answer to the question you posed in the title is "yes" - however we had thought that you were asking about bigger regions, Asia vs Europe or something. As an example in that category, the Haas brand name is not that strong overseas, and brand recognition of school tends to matter quite a bit in certain industries and countries. We often caution people interested in certain international careers that they'd do better with other schools - even, surprisingly, a school like Cornell which isn't considered as strong as Haas is in some respects.
But to your question: It sounds like you're actually talking about a form of
ethnocentrism - in this case, people being closed-minded about other REGIONS without regard to the facts. You shouldn't go to UNC because it's in the South??? That's a little ridiculous.
That being said, everyone does have their own biases and most of us don't ever recognize them, so we're not going to hold that against anyone. We honestly don't see that to be the norm in Silicon Valley though. Much more commonly, the bias is in favor of a specific brand name - see comment re: Cornell v. Haas above. And this is universal, not limited to Silicon Valley.
The reason that Silicon Valley might hire MBAs from the Pacific Coast schools more often (to the extent that they hire MBAs at all - that area isn't known for loving MBAs in general - but that is a discussion for another time) is that once you get out of the Top 10 schools, most MBA hiring is local. There's only three really good schools in the West (some might say only one) and they attract students from all over. A chunk of those students are going to disperse back to "all over" when they graduate, and another chunk will stay in the region. However, even combined from all schools, the chunk that stays local isn't a huge number - maybe (complete random guess) 400 (?) or so out of the 1,000 grads that these three schools spit out each year. That's not a huge number of warm bodies for recruiters to be working with when you think of all the companies in the western region - there isn't another bschool until you get to Chicago so that's a pretty wide territory, if you think about it.
The reason that someone might favor a Northeastern school is simply prestige; you've got history and associations. The NE is more frequently associated with Ivy League.
If you're asking, "Should I go to Amherst to get an MBA job in Silicon Valley" we'd say an emphatic NO. This is an unlikely path forward. You'd be on your own for recruiting. We're highly skeptical that Google is on campus there. They also don't seem to be recruiting at UNC K-F -- but they sure are at Duke. So is Apple.
There's a lot more companies in the Valley beyond those two but you can use them as a proxy to see where other quality companies would also be looking for talent.
It's true that there are fewer great bschools in the Midwest and the South - but there's a handful. Pick your school based on THE SCHOOL - not the geography. Geography only should matter for YOU, in terms of where you want to live for a couple years and the type of bschool experience you want to have.
EssaySnark