So... I did it. I wore my Tykables shortalls out - I took my dog for a walk in the park, which in fairness wasn't particularly crowded, but we did run into a group of old folks walking their dogs. The dogs said hello, so we naturally chatted. It didn't come up at all, nobody gave me weird looks, nobody seemed to care. And it reminded me about what it was like buying diapers in a store as a teenager, when you get all nervous and antsy until you're well out the door and in your crappy first car... and I came to the realization that it was very likely that nobody cared.
And even if they did, so what? It's a functional piece of clothing and I live in the Southern US. It's hot. Oh well. I figure I'll wear them out again and own it.