Some monitors do have speakers, and not having enough functionality for a remote to be needed is exactly why someone would get a monitor. A remote for a non-smart tv these days would basically be an input control and volume. Everything else would be controlled by some other piece of equipment that would need its own remote/app on your phone.
I used to have a Nintendo WiiU connected up to an old computer monitor with integrated speakers. The WiiU has no volume control of its own, so the only way to change the volume was by going through a series of menus using the crappy unreliable light-sensitive (yes) buttons on the bottom of the display. It was a pain in the neck, and a remote control would have solved that problem nicely.
