Use sand not concrete as machine weight?

Up for discussion. A double skin plastic tub front ( bit like a Newpol washing machine from the early 1980`s ) but instead of concrete which tends to crack, as many a Hotpoint owner knows only too well with their rather pathetic and unreiable front weights, use loose sand instead capped off with a rubber bung. Since sand has a s/gravity at a pretty constant 2.65 ( quartz ) whereas the recent idea of using water as a weight with all the leaks that will entail is only 1 so by volume you`d need less space for a given weight if sand is used. No shortage of sand, better than water, more reliable than concrete, cheaper than cast iron.