I too mend my socks if they are favorites. If not, they go into the rag bag for more use. Of course, I try to salvage my hand knit socks as long as possible. We are such a wasteful nation that I try to do my little-itty part.

NO, socks are not that expensive to replace.

I just darned a toe rip in my white sock the other night using a darning egg of which I have 2. Like thin socks so thought it was worth the few min it took with white thread.

I find that the sock is so worn that it's not worth the effort. It usually allows for one more wearing before another hole develops.