Yeah, this one's a no-brainer! You can let a xeriscape garden fend for itself, and some stuff might survive. But if you want to grow food crops it seems pretty obvious you have to water. Mind you, they probably shouldn't be planting watermelons either! Too demanding.
Does your County Extension service offer any free classes on installing your own micro-irrigation? It's easy, cheap and very water-efficient and I think it's as much fun as playing with Lego. Surely your 'lazy' neighbors aren't all that lazy that they wouldn't install just a small area of efficient irrigation and buy a timer for it?
