https://en.wikipedia.org/wiki/Trampoline#First_modern_trampo...
I think this is really just a case of lawyers being super-protective. It also pays well, I'm sure.
I think a words like Humvee or even Google have coloquially already lost their meaning--their meaning is polymorphic, it's only a matter of time (100 years is a matter of time) before a better Humvee or Google not released by the original product designer comes along that people will call Humvee or Google anyways.