I understand why they do it, but I cannot ignore that you lose the incentive of visiting your friends and their kids when they always take that visit as a way to treat you like a babysitter. Yes, I accept sometimes looking at your kid while you take a nap, just don't make that the usual experience for years on end, though. I'm lucky, as my friends always understood when I pointed that out to them, but I'm aware that this may not be the common reaction.

Admittedly, I don't know that particular case from practical experience, but yeah, well, that sounds very symbolic for what I meant.