It's important to note that the vast majority of people who will own and use Dai have never and will never interact with the Maker protocol or CDP holders. You trade ETH to Dai on Uniswap and go about your day. You trade the Dai to ETH on Uniswap later. I'd expect most people just to go from fiat straight to Dai and back as well.

Maker itself is a system for the professionals and most users won't even know it exists and won't have to.