I agree those boards are distasteful but as others have said "to each his/her own" and "you don't have to buy it."
Sadly, those prints will sell to some misguided individuals. I once bought a t-shirt that said "Bad Mother f'er" uncensored. I liked it because I like that scene from Pulp Fiction when Jewels tells the diner robers to fetch his wallet. Anyway, I never once wore it out of the house except as an undershirt. The one time I did wear it out it was on accident and I felt so uncomfortable. The kids don't need that kind of example set.
I believe that most people would find boards like that offensive and I even bet there are a few mountains who would ask those folks with offensive stuff to leave. I would hope generally people would stand up for unoffensive stuff. Go snowboard down your front lawn.