Sea Lamprey are a serious invasive pest that almost caused the total collapse of the Great Lakes fisheries.. And you are right it is not their fault but they are OUR problem...We caused it and need to own up to it.... responsibly.
Changing anglers attitudes is a difficult thing to do. Most kill every lamprey, every gar, every Bowfin, Every Mudpuppy etc.... Due to a general ignorance of ecology and thats what they where told by their parents which where taught by their parents. Education and outreach is successful in changing biological perspectives.
The number two big problem is we have Native beneficial Lamprey (such as the one in focus on this thread). Native lamprey populations are in serious decline across large portions of their range. This has much more to do with habitat destruction, damming, and siltation issues than angler hostility but given the situation is is deemed important to raise awareness and understanding of these little known fish however one can.
Native lampreys are a very important component of the ecosystems which they exist.
I do not suggest trying to keep these fish unless you are serious and in the advanced stages of this hobby.. They are not very good aquarium fish in the traditional sense at all. Additionally the legality issue of them is very tricky in many states. It is best to enjoy them if you run across them and then release them..