Amazon also does this right? But unlike kindle, kobo devices can easily have libre readers installed on them that can read whatever format you like. I threw koreader on my kobo and haven't looked back. It communicates with my private opds server to download books I have, ah, acquired, and converted to epub. Or sometimes PDF.
I think it can even read MOBI though, i vaguely remember accidentally uploading some to my kobo without converting and reading them before i realized the conversion step was missed.