Yes, he's wearing them, honest! 
It's as inthesticks & maryz said -
come in, shoes & sweaty socks off, sit about in bare feet for a bit, leave socks in living room
go upstairs & put clean socks on, sit about in those, take them off for a shower & leave them in shower room
pad about barefoot for a bit, put more clean socks on, maybe go out & see friends, come back in, take shoes & sweaty socks off - somewhere in the house, could be anywhere
watch TV, go up to room & do homework or play guitar or talk on FB, feet get cold, put 4th pair of socks on, take those off at bedtime & leave on bedroom floor
(inthesticks, I've started getting those plain socks with patterned/coloured heels, they are fabulous for matching up (or for finding out you've lost a mate in which case you can mis-match quite happily) eg \link{http://www.marksandspencer.com/Freshfeet-Cotton-Contrast-Silver-Technology/dp/B003KA2OS8?_encoding=UTF8&categoryNodeID=43371030&node=66670031&mnSBrand=core&ref=sr_1_5&qid=1285525280&sr=1-5&rh=&page=\these} & they come in plain, single-stripe, multi-stripe etc so you can allocate them to individual sock-wasters)