The first Hobbit movie set me against 48 fps for this reason. The weapons on the characters backs bounced around as if they were made of foam -- because they presumably were made of foam. 24 fps hides this imperfection and lets your brain fill in with a more appropriate interpretation.

The same bugs me about rerenderings of 90s television at higher resolutions. The sets suddenly look fake -- because they are -- but in standard definition you simply can't tell.

Any improvement in media fidelity must be accompanied by a complementary improvement in set/makeup/prop design to avoid this problem. Problem is, at a certain point -- this extra work simply surpasses what is relevant to tell a good story, and is left undone -- and high fidelity reproductions belie this shortcoming.