"That's a good recipe for buyer's remorse. It's especially worse with DD though. If you had buyers remorse after buying a retail game, at least you could sell it to get some of your money back."
That wasn't your argument though, steam is cheaper sometimes, especially with it's bigger packages like the new edios one and the sale on a game every weekend, and some people think it's more convenient to have it on the server so they don't have to keep track of the physical copy. It obviously has it's advantages for some, if you don't like those advantages fine but don't try to shit up a steam thread to when they're are clear advantages for it and obviously disadvantages too like anything else.