In addition, renting a film vs seeing a film in a theater is significantly cheaper. If I want to take my family (2 adults, 2 kids) to a movie in a theater, it usually costs about $40 - and we don't even buy popcorn or anything else. This is just "get your ticket and take a seat" costs.
It's been awhile since I actually rented a film from a physical video store, so let's take Amazon VOD rentals for our cost example, Renting an HD movie costs about $4.99. Buying it costs about $20. Buying the Blu-Ray or DVD costs about the same amount (depending on what package you get). More often, though, we rent DVDs by taking them out from our local library. Cost: $0. (Ok, we're paying for it in our local taxes, but that money is getting paid whether we use the library or not.) With the cost of renting it (and especially with buying it), you can watch the movie again and again without paying for another ticket. This just increases the savings.
There are definitely times where we want to see movies in the theater, but these are the exceptions rather than the rule. We go to movie theaters about four times a year, but rent/buy WAY more movies than that. Even before you get into the annoyances of other people in the theaters, the pure cost savings combined with my limited "entertainment" budget means renting/buying trumps tickets.