I would always make jokes about them, but it was all just for fun. I'm an adult male who still loves The Lion King and reads Warrior cats, so I never hate on anyone for loving something that, to the rest of the world, may not seem appropriate to their age group.
Now that I'm a brony, I still poke fun about it but I use myself as the target. All of my non-brony friends know I watch the show, so I'll make fun of myself to get a laugh. They're accepting of it though so it's all for fun.