I took up your question with a lead developer of DMD and here was his answer:
"What is bitcoin dash ethereum being backed by? not even fiat is backed by a gold reserve. DMD has all that bitcoin + all top10 coins has. And DMD has more
DMD has -as one of the few coins - a finite coin supply and a infinite coin rollout.
DMD provides 2 ways to earn semi/passive (need a node running) income via POS and masternodes. And DMD will never stop developing the coin to establish a serviceplatform on top of what DMD already has and then build services and apps around the DMD ecosystem. " I hope that clears up slightly why I - DrDMD - is heavily invested.