what i did was, when i saw a movie i wanted to check out coming in 3D, i paid the 9.50 to see a regular movie.
left almost halfway through complaining the kids in the theater were being loud and if i could get a rain-check and because i wasn't a dick about it they gave me an extra rain-check.
then used the rain check on the 3D movie.
bong! 9.50 for a 3D flick and the extra ticket compensated for the mileage lol