The point is...your comment implied it was inappropriate for us to care about what others were doing because it's none of our business.
Well the "liar loans" were an example of how that can play out. On an individual level, it's not my problem if the neighbors are in over their heads but on the larger scale it can still impact me, so it is my business.
No, I don't expect the RV loan industry to blow up the economy all by itself but same thing is happening with boats and houses (again) where things are going into a bubble...so it's very legitimate to look for the canary in the coal mine.
PS: While the banks certainly played along, a large number of borrowers were plenty guilty of taking out loans they had no reasonable expectation of paying off.