How To Make A Quality Asshole Out Of Yourself:
1) Simply pick a seat that is noticeably filled with someone else's stuff.
2) Remove and relocate that stuff.
3) When the person returns expecting to sit in his or her seat refuse to move.
4) When the person explains how that particular seat was "saved," refuse to acknowledge that particular cultural norm.
5) When refusing to acknowledge the practice of saving seats be sure to invoke the power of history and let the person know how many years you have been coming to that particular establishment and how you resent the presence of so many people at "your" theater.