Gun control is a great example that seems to confuse a lot of non-Americans. To your average San Franciscan, who has never used a gun and has no particular reason to use one, restrictions on e.g. magazine size probably seem quite reasonable. But go to an agrarian Texan rancher, and the situation is entirely different. Good luck thinning out a stampeding herd of wild hogs with a ten round fixed magazine. Similar situation with pot; the average SF resident is probably fairly familiar with it, whereas the rancher probably isn't. In either case, ignorance breeds irrational fear, which is a bad (but unfortunately likely) foundation for laws.

So yes, many regulations are not sensible, and it's harder to get away with in the US because the US isn't a monoculture. Even those regulations that are sensible (by whatever metric you like) are likely to anger some non-negligible group.