>>The opportunities to hunt are just not that available.<<

I'm sure that is true.  When I was growing up I could hunt on a whim.  So long as I had my work done I could pick up a rifle or shotgun and go hunting almost any time.  Now that we live in a city going hunting is a major undertaking.  Since the kids don't see their friends doing it routinely (as I did) hunting really isn't on their priority list.

 >>License fees and complicated regulations probably impact the number as well.<<

I think that in-state fees are still pretty reasonable, but hunting regulations have reached the point where I find myself hesitant to do some types of hunting because there is so much regulation, and not all of it clearly written, that I'm not sure whether what I'd be doing was legal or not.

Not exactly hunting, but perhaps illustrative of some of these regulations: I recently found out that it is illegal to kill a snake in Virginia.  (Though I believe there are exceptions for self-defense.)  I checked the hunting regulations and didn't find a word about snakes.  I then contacted a friend who is a game warden.  He explained, "Basically if there is no set season or listing as a nuisance species the animal is not to be taken." 

Now I believe that snakes play an important role in nature and I don't kill them unnecessarily, but I was shocked to find that doing so would be illegal.

A long time ago I went antelope hunting in Montana.  There was a story going around at the time that a young lady had shot her first antelope and was still standing over it when a game warden arrived.  According to the story, the warden noted that she hadn't yet tagged the animal and that he wrote her a ticket and confiscated the animal.  I have no idea whether that is true, but I'd have hoped that a game warden finding a young lady with her first antelope might have cut her a bit of slack and instead of writing a ticket, simply reminded her that the animal should be tagged as soon as possible.  It's difficult to be enthused about hunting if you are in constant fear of violating some regulation.