The last time that happened to me I asked if I could see what time it was on the girls phone,(EDIT) because she couldnt stop hcecking it and because when it went off it made one of those sounds that 'adults" arent supposed to hear, then put it in my pop and threw both away before telling her thank you and kindly sitting back down.
Of course he boyfriend (needless to say the girl herself) didnt take kindly to it, so after we got through the pleasantries of what the fuck man, dont you know how much that phone cost, and of course the all too important and classic You're gonna pay for doing that (to which I politely replied theres a movie going on and it says turn your phone off, not off hand but I could take a rough stab at it, and I doubt I'll be doing that), the conversation took a slightly violent turn where he got up to hit me and then my friend who was easily 30 lbs heavier than the boyfriend (and thus 40 lbs heavier than myself) told him to sit back down before something bad happened.
In the end the manager was called in, looked at me then at her and him and told them to get out and we will not be refunding your ticket (as the boyfriend had broken the cupholder on the seat in his uncivil actions), nor would they pay for the phone or would they testify against me as they had no real knowledge that i had done it and would not subject to heresay.
Two years later and Im still going to movies and enjoying them. So really, whos being the childish one here OP, in that youre not going to a movie ever again just because a man didnt want to be in the movie and you couldnt be bothered to move or talk to him and ask if he would kindly stop, instead relying on his abilities as a mindreader to pick up on the problem and correct them. especially when you cant be bothered to go get an usher (because honestly, no one cares if you walk out as long as youre polite they'll just assume youre going to the restroom). ANd when you cant let it go 3 hours after the fact.
Besides, I dont know a theatre that does assigned seating and I know that in the one I had worked at we had rules against filling every seat (because we had more than the maximum fire safety occupancy stated people could be in for some reason), so either you need a new theatre or need to find an usher and ask if you could have a refund and see the movie on another date.