I have been using Burlington socks for some time and mixing in the Costco socks for a few months. Both are USA made and thick and hold up well possibly the Costco socks are made by Burlington. The Costco socks unlike most are also available in XL, I use L but XL may be better for some. $1.66 a pair. Crappy cheap socks are no bargain if you get blisters. http://www.costco.com/Kirkland-Signature™-Men’s-Athletic-Sock-6-pair-White.product.100160932.html
I have the CostCo Socks in my BackUp Preps a couple of dozen Pairs.... Lifetime supply.... for us Old Dudes...
I have never bought Costco socks. So they are quality? I hate buying socks then have them stretch out and get all thin really quick.