19. He'd never let anyone take your spot in line.
Trying to see a summer blockbuster on opening weekend can be frustrating when you have to get to the theater early to stand in line. Plus, don't get us started when some bozo tries to cut! Luckily, Sheldon isn't the kind of person to let someone get away with that bad behavior, so go ahead and step out for some popcorn because your spot's safe with him!