Not babies, but any kid over the age of 2 who is at the grocery store in his PJs, I judge the parents.
I did too. I was all smug about my daughter, N, who would wear anything I put out for her. Super cute dresses, perfectly matching outfits, bows, the whole deal. I was like "come on parents, if I can do it, so can you."
Then I had my headstrong younger daughter and learned a lesson about picking my battles. She's pretty much in underwear only at home (a battle I picked, and won, because there is a bare minimum clothing requirement for sanitation purposes). If I get her out of the house in any weather appropriate clothing, I consider it a victory. Pajamas fit that bill, and are the path of least resistance, so that's what she wears a lot. Oh, and she's 3. She's also the kid who goes to preschool with hair flying everywhere, looking like a clown (there's a reason I don't post in bootd) giving exactly no fucks about it. And frankly, neither do I because, again 1) she's clothed, and 2) she's now at school and happy, therefore I'm happy.
My not yet 2 week old is sitting next to me in her car seat in a long sleeve onesie. I only have one pair of leggings/pants that fit her. Whoops. I certainly have never considered judging anyone for this.