Not very often, no, but not just because I know how they will end. I watch movies for the experience. If I want to have that experience again, I rewatch a movie. Birdman was an amazing experience to watch in theatres so I rewatched that later on, finding new details along the way while still being immersed in the story. Rewatching is not the same experience as having a movie spoiled even though the information you have going in is similar. Because SW:TFA was spoiled for me I didn't have that sweet and rare experience of going in completely blind and enjoying a movie for what it's worth - nor can I relive that experience by rewatching.
I will say that I tend to determine what my "favorites" of a [thing] (music, books, films) are by how much I willingly, even unthinkingly, revisit it. A good album is one I can listen to on repeat 20 times. A good movie is one I am willing to watch again, and so on. Before I was 19 or 20 I had never read one book besides Lord of the Rings twice. I am not saying that going in and experiencing a surprise is not without worth. However, what I am saying is that it matters more to some people than to others. I would also put out there that asking others to spoil Star Wars is as much a request born from perverse pleasure as from anything else - a lot of true fans are so against spoilers that to eagerly ask them for such makes them squirm and uncomfortable. I got several "Are you kidding me?" stares from people that I asked to tell me what happened in the new movie. I honestly think the request should be viewed as much as a judge of character and/or value than as a simple question, "tell me what happens." I think saying, "Tell me what happens at the end," tells you as much about the person you are addressing as it does about yourself. I already know how I feel; I already know I won't be terribly bothered if you tell me what happens at the end. However, seeing how you react to this tells me more...both about you, and the movie (or book or song or piece of art or whatever). The more quality that a person perceives in a product, the less likely they are to willingly spoil it. The more emotional investment a person has in it, the less likely they are to want to spoil it. Sometimes, it's fun to make people uncomfortable. Asking for spoilers makes people uncomfortable.
I can't disagree with that. I'm just surprised that there are people to whom it is worth none. I knew someone who, when walking in someone's dorm for the first time, would loudly say "So this is where you masturbate, isn't it?" - juuust to make people uncomfortable.I am not saying that going in and experiencing a surprise is not without worth. However, what I am saying is that it matters more to some people than to others.
Sometimes, it's fun to make people uncomfortable.