You mix up patents and copyright. You are right with copyright - I copy your code, I know I do that and that's why I'm ok with copyright protection. With patents people don't steal it - they don't even know you own it in most cases. Because software development would grind to a full-stop if you had to check every time you code something for all possible patent violations. Even lawyers have a hard time figuring out which code breaks which patents - software developers simply have no chance doing that on their own anymore. Patents are the wrong protection scheme for software for the same reason they are wrong for example for protecting book authors (imagine "Happy Ends" or similar ideas would be patented...).