Often new technologies seem like a better idea than they really are, because they are fun and exciting when sampled in small doses, but become less pleasant with prolonged exposure.
It’s like the first time you tried cream soda, and you though, “This is amazing! Why don’t we drink this all the time?” And then you realized you couldn’t finish the bottle.
3D cinema is susceptible to the Cream Soda Effect. People often watch short demonstrations and enjoy the novelty, and then spuriously extrapolate that they’d like to see a whole movie in 3D.