A lot of these laws are out-of-date. Many have been eliminated and others go unenforced unless the hunter is confrontational or the officer "knows" he has broken a law but can't prove it. However, it is our duty as hunters to know the rules and make sure we follow them. Having written that, I'll make sure to check my favorite broadheads before venturing forth into another state this year.
I've had my license checked in Wyoming, Ontario, and Indiana. I've never had my equipment checked.
However, with the vast majority of these laws, we can blame our own (or our ancestors) for them. You can bet your bottom dollar some archery expert(s) was succcessful in getting his perception of ethical equipment written into the laws.