Strabismic people that do not correct the problem before ~8 years old do not have 3d perception using binocular disparity (that is,estimating depth in short distances using only the differences between the images of the two eyes). For me (never had surgery), I cannot see 3d dot stereograms or 3d movies (I ve never actually watched a 3d movie, but I have tried seeing blue/white 3d images in vain).

There are other ways to perceive 3d, such as motion parallax, so yes, we are normal people too :)

That's the reason i am not excited about 3d movies and hope they keep making 2d versions of them