define "cartoon" do you mean like a non-human but very erotic drawing of an adult woman? Or do you mean like Sponge bob? Do you see the difference?
Maybe it's cheaper for a non-content person to just hire a designer to create a toon logo than it is to pay a chick for a photo session.
Maybe a toon logo is less offensive to softcore sites.
Maybe someone drew it for me, because they wanted me to use it in a TGP, but I never did. SO THERE! Happy now. (The following toon is not for kids)
