The next time you're headed to the lakes for two or three weeks, don't burden yourself lugging a full wardrobe for each family member. Scrub-a-Dub's prices are reasonable enough, that even having to wash laundry every three or four days will not put too much of a crimp in your vacation budget.
Typically I go every four days and spend $5-$7 to do laundry (including beach towels) for my family of six.
This laundry is maintained and clean. The machines are well-functioning, and they do not mind if you leave while your loads are processing.
Typically I drop my things off in the washer, jot down to the library, come back thirty minutes later, pop them in the dryer, and head back to the library.
They also run a putt-putt golf course for those interested in entertaining themselves in that way while washing their laundry.