why does everyone have cartoon pics as their facebook pics?

Just like how all the girls were trying to end Breast Cancer or domestic abuse by making their FB status a sexual innuendo about liking their purses at a certain spot. For example "I like it in the bathroom". I have no idea what that accomplished, but this gave me a chance to post megatron as my FB picture.

The year before that, it was "Post your bra color" -_-

And all the girls were pretty much being peaches when anyone asked them why they were doing it and none of them wanted to say why.