For hard ground use the long lag bolts and a cordless drill. Some people have switched to that method altogether.
Is that how you set yours up... lag bolts + washers and drill? This is a good suggestion that I've seen before, though we don't travel with a cordless drill.
I can think of a few times we were on slickrock type surfaces or shale where even this probably wouldn't do it. For those, we just used a different tent or slept inside our vehicle.