Vulgar game day tees: what happened?

I don't know about the south, but in my formative years (mid to late 90's) vulgar game day shirts used to be common.

For example, when I was about 13 or 14 I bought a tee at a Colorado/Colorado State game. On the front, it had a buffalo on it's knees presumably blowing a ram with sun glasses standing akimbo. On the back it had a ram in the same position only nuts were visible and the buffalo was cupping them. Great shirt, my mother made me throw it out when I got home. I also remember a game where Wyoming had a "Rape the Rams" shirt (pre Brokeback Mountain) of a Cowboy presumably ready to, well, rape a cowering ram.

I remember seeing other at games I went to in Arizona and even Nebraska but have not seen them for years. Maybe it was just the height of the Big Johnson craze sweeping America?

Any insight would be appreciated.