I wear Chaco sandals with my shorts all summer.  I do almost everything except clean out bins wearing them.  Spray fencerows, run equipment, drive truck, cut thistles (learn to keep your foot out of the thistle, duh!) and almost everything else!  My back never hurts when I wear them, they have great support.  Probably the most comfortable shoes I own!  They are not cheap! But, like with all good footwear, you get what you pay for!!!