I don't think there is any appreciable difference, at least with the Steam example, as to review it you have to have owned it and refunds are neither easy or plentiful. Besides they were usually bombed for things relating to game login changes or DRM changes not on a whim like free apps on Google Play often are (which Robinhood is).

That's not to say Robinhood didn't deserve poor reviews or Steam hiding it is good but it definitely has seemed to strike more of a nerve with Robinhood even though both were very similar.