I find some of them THINK it is their goal, but ultimately are not digging into their desire to kill one deep enough. I think the idea of killing one or just having to prove their existence to save them is naive to start with. If you kill one I am pretty sure it is certainly a illegal thing to do, seeing as how they are at least a undocumented species and possibly even a sort of human(which would be murder). You aren't going to be famous for it, you are going to be infamous, you aren't going to get rich, you wont even get to keep the things body. The body will not be the killer's property, but the US Governments for sure, and the situation will go from there. Considering the damage their discovery WILL do to the lumber industry(If not numerous others), it will likely be considered a issue of national security. Could ruin alot of lives, not to mention the bigfoots once we start trying to control and fidget around with them like we do everything else. That same impulse to control, manipulate, and fidget with everything is the same impulse people have to kill a *Insert mysterious/new species name here*.