1. No arguments
There are so many opportunities for arguments to break out when you go to the cinema with someone; arguing over what to see, where to sit, whether it was good, bad, boring, stupid, amazing, sexist, expressionist, neorealist, postmodernist, smackinthemouthist. Films are divisive and not all of your friends will share your refined taste or expert opinion – you can start wanking now.
Head to the movies alone and you will endure none of this. You can watch exactly what you want to watch, where you want to watch it and be 100% right, 100% of the time. You are anyway, of course, but this way you won’t have anyone to question your divine wisdom.