...to be 21 and never bought a pair of pants or socks for yourself ever?
I've had the same ones for like 3/4 years (they've obviously been washed a couple of times in that period), same goes for socks. I've got like 15/20 pairs of each, so why should I bother.
The only time I get new ones is when I go home from uni and my mum goes something along the lines of "Oh, these were on offer in Tesco, so I picked them up for you.'
Personally I don't think it's wrong. My friends think otherwise.