hp could get a cert for 15327c5ba80d1b8933.hp.com and make it resolve to 192.168.0.5 (your printer).
But now you are running TLS, so the address conflict would just yield a cert error. (If the other guy plugged his network or printer into yours, that is)
And at the same time, I've introduced an internet connection dependency and a 3rd party dependency. What happens when they decide to stop updating that cert, to save money?
Or use addresses like https://192-168-1-1.hp.net (https://192-168-43-123.hp.net, https://10-20-30-40.hp.net, and so on) and a wildcard cert. No harder to document than telling people to go to http://192.168.1.1.
Though they should be more careful than to use to top-level domain as they need to include the private key in the device unless they have the devices call out to have a new certificate generated, perhaps 192-168-1-1.internaldevices.hp.net and so forth.