Your premise here is that young Americans can't handle this? Young Venezuelans and Dominicans appear to be able to survive it.
It strikes me that it may well be harder for veteran ballplayers to make this kind of adjustment than for a 19-year-old. Veterans have expectations, based on their years of experience, that a kid right out of high school may not.
As noted above, Latin kids go through major culture shock all the time, and seem to be OK. For that matter, take an urban black American kid, or a kid from suburban San Diego, and drop him into some little town in the Appy League (or Williamsport!), and you're going to get a bit of that, too.