If Musk is able to help bootstrap passage to Mars, I can fully see a non-trivial percent of colonists willing to take on 5 years of indenture and hard, dangerous, labor in exchange for passage. I can even see the rich "sponsors" staying here on Earth until Mars is suitably developed for comfortable living.
They are provisionally willing, I'll put more weight on that declaration once they are on their way.
I also speculate that there are a number of people willing to go for historic prestige (or something like that), while most potential indentured tickets would have to see some pretty terrific economic prospects at the other end of the contract (it's warm on Earth and the air is free).
