It looks nicer. What you’re suggesting has either a brick attached on the back and/or at least two cables (but probably more).

>a mini attached to the back of a monitor

It is ugly. Especially i places like a reception, where the back of the screen is facing the customer. Plain and simple.

Aesthetics obviously.. engineers and tech nerds are not the target audience for this machine.

No, but if you're on a 3-5 year refresh cycle and this is your year, it'd be lame to not have the latest chip!

It's simpler and better for both hardware makers and buyers to just keep refreshing instead of trying to get clever about who deserves the current series of chips in their form factor, assuming the refreshes are of similar cost, utility etc.

These places aren't going to care about saving $200 on a machine that will return an order of magnitude or more than that in sales per hour

Most I've seen are just used to RDP into a Windows box anyway, so probably not. That does make it a little strange that no one seems to design a nice looking terminal PC.