I am part of a startup and I can tell you one thing from what I have seen the "CEO" and the people are doing in it. Everyone seems to put all in the effort and everything but generally, the output generation is low. What I mean is, the 80/20 rule applies here a lot. In startups, I have found that it is more about doing experiments and doing them rapidly.

You should take a look at what they are producing and what their current revenue is. That should give you an idea, if putting 80+ hours is REALLY helping them or not?