My personal number one issue with Steam (aside from the obvious fact that it's still DRM at the end of the day) is that I think their family sharing feature is kind of bullshit. You cannot let somebody play a game in your library and be able to play yourself another game in that same library at the same time.

There is no good justification for this restriction and it makes that whole feature sound more like a PR move than something that was really released to help the consumer.