I'd find it really odd if DH came home with some new tights for me because he'd kept note that I needed them, equally, it would seem odd if I did the same for him.
For those who buy them, did your DP/H ever ask you to take on this task or did you just randomly decide that it was a wife/girlfriends job to buy their socks? Surely before you were living together they managed to make sure they had socks and pants themselves? Or is it they went from their mum dressing them to their DP/W doing it with never actually chosing the socks they wear themselves?
Just seems a strange thing to do without being asked. If DH asked me to pick up some socks for him while I was out I would, but I have no idea if he needs any. I don't monitor his sock situation.