I have a deep, dark secret: I own (and have worn) adult sized footie pajamas.
I have NOT worn it in public, though; I have only worn it at home, to sleep in.
I thought it would be a good idea. I often get cold (well, when it's cold) and such pajamas seem to keep children warm so I thought I'd give an adult sized one a try.
I bought mine at Meijer in Michigan (a grocery and everything store).
At first they were great; I was nice and warm.
Then I freaked out because I was too warm. I feel like the Incredible Hulk when I get too warm; I just want to rip off the layers and cool down.
It is not easy to extract oneself from footie pajamas quickly. I haven't worn them since.