Why do people judge a movies popularity based only on the box-office?

Seriously, most people are either too poor to go to the movies that often or simply just don't want to pay a ridiculous amount of cash to watch a movie that they can buy for about the same amount when it comes out on DVD.

I mean, I really can't blame people for not wanting to go if they get landed with an overpriced, s***hole with limited snacks and soda options that are so overpriced it'd be better off sneaking your own popcorn and drinks into the theater.

Seriously, I was once at a theater that charged $8 for a SMALL soda, and the options were Pepsi, Diet Pepsi, and Sprite. Three f***ing soda options and you have to pay that much for it? Yeah no.

Judging a movie's popularity should be more based off of it's overall sales -.-