Seems to me there have been previous post on Rick's Website and this Forum where people "bragged" about bringing their hole-iest, most worn-out underwear, then wore and discarded them as they traveled, like a sort of undergarment trail of breadcrumbs, something for the maids to dump with the trash each day. That worn-out underwear might not have been the most comfortable thing possible, either.
You could bring brand-new socks and underwear and toss it as you go (it's your travel money), and you could save time and having your hands in soapy water, and your suitcase would certainly be lighter on your way home than when you arrived (unless you bought disposable underwear and socks over there in Europe), but I will say the underwear from Ex-Officio is comfortable, ventilates well even in heat, and dries amazingly fast. Regular socks take more time to dry, but comfort is worth having clean, proper socks to wear. If you're renting a car, lay your socks in the back window well. If you're on the move without a car, stow your still-damp socks/underwear in a mesh bag to allow air to circulate, and put them in a Zip-loc bag if you need to keep them from getting other things wet, them pull them out to air-dry again at your first opportunity. A hair dryer can sometimes help speed up the drying process, if necessary.