In M.night sham-aliens there's a scene in which Rick is playing with morty while collecting the crystals. At the end of the episode it's implied that Rick knew he was in a simulation the whole time so, rick was aware that the morty he appeared to be having genuine fun with was a simulation. To me, this scene speaks to rick's character, he does want to have an emotional connection to morty but, he's too cold and detached to actually have one. I think he chose to experience the feeling of having a connection with morty within the simulation instead of the real morty.