1. Spider-Man is able to crawl on walls with his costume on
We all know how the story goes. A radioactive spider bites one of the brightest (and unluckiest) teenagers on Earth and suddenly he gains powers such as super strength, spider-sense, and the ability to crawl on walls. It all seems to make sense until you stop to consider... Peter Parker shouldn't be able to climb over any surface when wearing his costume. To understand why, let's discuss a bit of biology, shall we?
Real spiders' legs are covered with many small hairs, and each one of those individual haris is covered in even smaller hairs called setules. According to science.org, spiders can stick to walls thanks to the "electrostatic attraction between the molecules" of setules and the surface they are over. Sam Raimi's first Spider-Man movie even went as far as demonstrating how Peter grew these setules on his fingertips after being bitten by a radioactive spider:
So why does any of this matter? Well, because the wall-crawler wouldn't be able to wall crawl if his hands were covered with gloves. The setules in Peter's fingers wouldn't be in direct contact with any surface, making this superpower completely useless.
There's an argument to be had that maybe the hairs are so small that they can go through the fabric of Spider-Man's gloves. But if that's the case, then how can our friendly neighborhood hero stand straight over a vertical wall and still stick to it? How do any of the things we've talked about apply to the shoe soles of Spidey's costume? We're sorry Marvel, but this is just one of those things that doesn't make sense at all.