Got them from a list off IMDB boards. Thought of them are really funny, so if you have more ideas, please do share!
#12 is by the funniest thing ever.
1. Batman uses his growling voice to hide his identity, not to mention it sounds more menacing.
2. Batman doesn't need superpowers, making him more powerful and nothing to fail on him.
3. Peter Parker is a dork who works as a pizza delivery guy while Bruce Wayne is a billionaire playboy
4. Batman has all the woman and money he ever needs
5. Bruce Wayne is a pimp and Peter Parker's been crying about the same girl for 35 years.
6. Batman relies on "his own scientific knowledge, detective skills, and athletic prowess.
7. Batman has a butler.
8. Batman won't go through an "emo phase".
9. When Batman goes through an emo phase, he cries man tears because the love of his life was blown up by his sworn enemy, whereas spiderman gets a gay chirguh haircut and dances like olivia newton john
10. Batman doesn't lose his powers or abilities because he doubts himself... Alfred just kicks his ass back into shape...
11. Batman doesn't live with his Aunt.
12. Batman doesn't have a best friend who becomes his enemy who becomes his friend who becomes his enemy who becomes suspected girlfriend's boyfriend who becomes his ally who helps him save the day because he is too weak to do it himself who becomes his dead friend
13. Batman does not need super-powered friends to take out his enemies... he's a one-man wrecking crew using other people as pawns
14. Batman's costume is way cooler.
15. Batman is like a bat that isn't blind or bound to caves. Spiderman is like a spider without posionous venom, 8 legs or the ability to inspire children's books my making messages in webs.
16. Batman has his own pizza, which spiderman has 30 minutes to deliver or he will get fired
17. Batman doesn't test his powers by waving his wrist and saying "go web go".
18. Batman doesn't get crowd-surfed by a random group of passengers on a train.
19. Very few of Batman's villains are closely tied to Bruce Wayne's life. Therefore, there are fewer opportunities for stupid coincidences and lazy contrivances, like Eddie Brock happening upon the same church in which Spidey is shedding his black suit.
20. Batman traveled the world to understand the criminal mind, while Parker can't get out of the dump he's in.