It isn't PoStake. Users aren't staking anything, they're contributing a few CPU cycles now and again and getting a little in return. Earnings, not interest, how much DASH you have in your wallet makes no difference. Provide service, get paid, same as MNs.
And we'll have to disagree about where the value to the user comes from I suppose. Currency is a tool, and like any other product that costs money to purchase, whether someone buys a tool or not depends on the value it brings to them, not how much it cost to produce. Though I'll grant you that while manufacturing cost may be a factor in affordability for most tools, what a unit of currency costs to acquire is irrelevant as that cost is reclaimed upon spending of said currency unit.
I think every single user should be a value-adding participant, this is a way of achieving that.