Karl, we all make choices and we have to live the with consequences of those choices. You chose not to register you boat and eventually got caught 3 years later. That was a risk you evidently were willing to take when you decided not to follow the law and properly register you boat, so don't be upset with the Minnesota DNR for enforcing a law that you willingly broke.
I'm not upset, the Minnesota DNR still isn't going to get my money, and I wasn't ticketed by the MN DNR, it was issued by a Wisconsin game warden. And it'll cost me at least $735 to register my boat, so I've got room for at least 2 more tickets.