Coax line going to power

I didn't think much of it at the time, but why does my Rogers Internet coax line go to wall wart?

I have gigabit, it seems a fiber line or similar is being used in conjunction with coax. The coax line is coming from outside and then going into a coax splitter like box, i also see a fiber cable plugged in but can't find the other end. Then from the box I have a coax line to the cable modem and another coax line going into a powered wall wart.

The rogers tech said this coax wall wart needs to be powered on at all times but what does it do? If i unplug it it does kill the internet so it is needed, maybe its boosting the signal or something?

not my picture but exact same wall wart
https://imgur.com/gallery/oZMKDzu