I haven't been to a movie in a chain theater in many years, for all the reasons you say.
However, I have been to see movies in small, independent theaters. They're more comfortable, the audiences are better behaved and smaller, the prices (although no lower) feel more justified in terms of the experience, etc. The only real catch is that they don't show new movies -- which, for me, isn't a real problem.
I wonder how many of that 50% are people who go to these tiny alternatives.