ARe my PUma Sneakers that trashed? (Worn them without socks for 4 Winters in a row)?

I have a pair of PUma sneakers that are 4 years old, and going on the 5th Winter wearing them without socks since I bought them. These sneaks are pretty much ready for the trash, but I really want to keep them for a while longer, because they are so comfy. They are totally trashed, by very dark insoles, which used to be white (they are now a dark brown color) the heel part of the sneaker is beginning to tear a bit on one of the sneakers, (The hole is like a pinhole and it is starting to get bigger a little bie, and they stink bad! As soon as I take them off my bare feet they would smell the minute I take them off. SO are these sneakers that trashed? Should I throw them out?