Not a Canon EOS user, but typically there are accessories called "dummy batteries" that take the shape of a standard battery, but is actually used by connecting to the AC socket. This way, the camera can be powered on constantly so long as the venue with the AC doesn't have a power outage.
I actually came across an Eos “webcam kit” at Walmart in-store that came with a USB cable and the AC adapter. Pricey at ~$90, but they did sell it like that.
Since all EOS R series camera's can charge their battery perfectly fine when connected to a USB-C PD charger the only thing that adapter 'fixes' is the software lock Canon placed on the camera which causes it to stop charging from USB when turned on. Smells like a software-defined business model to me...