Quite a few people don't have good depth perception, or none at all.
People with unequal strength eyes will oftentimes grow up without much depth perception, to no ill effect.
Yup, I fall into this category. I have good vision from the perspective that it's sharp and I can see at different focal lengths, but I had a muscle weakness in my eyes as a child (partially corrected via surgery). As a result, 3D doesn't do a lot for me. The loss of brightness and slight lens glare is not worth the trade-off for the (for me) barely noticeable 3D effect in movies.
But something like this seems quite interesting.