some have, but it really depends on where you're sitting, I suppose. I've bought a LOT of tickets over the years, so am pretty familiar with most of the sections there, which parts to avoid, etc.
It's Fenway-specific, but if you check out
www.preciseseating.com , you can get either a real picture or a 3D simulation of the view from every seat in the park. Shows what you can see, obstructions, etc.
Generally, as long as you avoid the Outfield Grandstand (on the Right Field side, the stuff in Left is fine, other than being the non-drinking, family section), or the last few rows of the Infield Grandstands, you're good. Most of the Right Field Box seats mean you have to crane your neck to the left a lot, but the view is decent and no obstructions, at least. I usually go for lower-row Infield Grandstand (anything below about 12th row is decent), or I've recently taken to liking the Right Field Roof Box seats, that's a nice seat for the money, and a better view/experience.