I wore one every year in high school for pajama day, and Halloween, and s few times to work for Halloween (including my mitten sleeper). Other than that, I often wear non-footed sleepers out for fast food runs, or under clothing for grocery runs.
I've worn to some babyfur/ABDL parties, so that's kind of public. I suppose I had to go out a few of the times to get from my hotel room to the party itself at furcons. It's not a big thing for me, although I like them okay. They're just part of appropriate clothing at a party and out in the real world, they don't serve much purpose.
I wear mine when I walk the dog in my back yard and go to the street to get the newspaper. I don't see them as that big a deal since they're sold in regular stores like Pennys.
I like wearing mine in public. All of the reactions are light hearted, picture a 6ft something guy wearing cowboy boots, a onsie and camo jacket to the grocery store. Heck, I picked up a friend from work in it. On a seperate note, I usually have a cheapo from the store under my work cloths(I work in the cold) and it helps a ton.