It's only hilarious because it's filmed in situations where the power dynamic is inverted from what it would be, i.e. it's social mis-calibration. In these situations, the vendor clearly has the power. It wouldn't be so funny if the client actually had the power to make these kinds of demands, and in many cases clients do have the power.
I have no idea why ethics enters into the discussion at all. It is an exchange of value, the person doing the work has the choice to take the trade or not, nobody is forcing him into it. It might be unreasonable to ask him to do it with no contractual protection, but that has nothing to do with ethics either. The potential employee could have made reasonable demands that if they got the client, that he would have to be on the team with so and so pay rate, but instead he says "That's not ethical"?