That PC is prime malware target (easy access vector since anyone can pay a few Euros to put a USB device into it, lots of opportunity for identity theft, plus the chance of accidental infection from all the thousands of random USB sticks it'll see in its lifetme), and there's no way the employees are security-conscious enough to engage in the appropriate mitigations (re-imaging the PC every day). And the scenario of the print shop employee (probably not paid very much) earning extra cash on the side by selling any valuable personal details they get isn't unimaginable.
While dm might hope you buy other stuff from them you definitely don't have to. If you are suggesting that their print service is a loss leader then please show some evidence backing that up.
Anyway, the 10c/page (A4 b/w) is still a good estimate, at least when I looked pre-pandemic (it might've increased slightly to 12 or 15c by now). A lot of cities, especially those with a University, have dedicated small "Copyshops" where you can walk in and get your 100+ pages thesis printed and bound within 20min. So the prices and service are aimed mostly at Students. It's true colored pages are significantly more expensive than b/w, but overall that's still cheaper.
And why does that matter? If there is a shop (idc how it's called) that lets me print for 10c then I chose that.
> Though already colored pages cost 55 cents.
The GP was about documents that you may have to send in / bring physically. I've never seen such institutions demanding the forms being printed on premium paper in color.