Indestructible Socks?

A few weeks ago I posted the following on Ravelry:

My husband loves to wear socks over his regular socks. Kinda like slipper socks but with a soft sole. My problem is that he walks a hole in the toe in no time (never takes him more than two weeks). He likes them thick and cushioned, so I always use worsted weight.
I have tried everything:
-knit the whole sole in the slipped stitch heel stitch
-knit on smaller needles to get tighter gauge
-knit 100% wool socks and felted
-reenforced the stressed areas
-used a wool/acrylic blend
-knit two strands together
-put leather sole on - to thick
-tried to cover in rubber/latex -he hates it
I am hoping to find good yarn that will last more than two weeks :-) I prefer to get my yarn at store rather than online since I like to feel before I purchase but ANY and ALL suggestions are welcome. If you have some tips and techniques that would allow me to knit socks that are longer lasting, I would appreciate those aswell.

I received a lot of good ideas and very valuable input. After discussing things back and forth, this is what I came up with:

so here is what I decided on trying:
-I bought real sockyarn (meilenweit and fortissima clori socka color) meilenweit has a cotton nylon blend and the socka is 75%virgin wool 25% polyamid
-I will knit this pattern
-I will use some nice and really soft yarn for the top and the sole will be three strands of sockyarn
-I will use the slipped heel stitch all through out the sole
-if husband walks through this I will stop knitting socks
-I will knit this sock a little tighter both in gauge and in fit. maybe if there is less room to move there will be less friction. less friction means less holes.
-if I ever get my hand on some kevlar, I will make bulletproof socks

If you are interested in reading the whole thing, click here

Right now the socks are in the wash. All my socks need to be machine washable and preferably survive the dryer. I will post pictures soon.