I had a similar unit in the past. I didn't have a need for it, just it was cheap and something to play with. It's ok for light tasks like using it as a video streaming client. As mine was an older model, it struggled a bit with 4k YouTube playback but 1080p was fine.
In business uses, these could be used to run a looped display of promotional material for example, or just a thin client used to access a server where real work gets done. Quite common in banking for security since data doesn't leave the original system other than what's displayed at the time.