Yea, something I don't think a lot of people understand, in general, equity can't be used in lieu of compensation for an employee (at least in most US States that I know of, pretty sure it is all but not 100% sure). This hasn't always been true, but the laws changed when a fair number of people were getting screwed with share class changes etc where they put in years of work to come out with not even minimum wage because founders/investors got greedy. Some founders who fought for their people didn't have enough stock to control the outcome so the board would vote the changes through over their objections. Hence why when you are doing these negotiations you have to recognize the person talking to you now may not be the person making the final call in 5 years.

There are ways around equity only with specific contracts & wording, but that is where the whole issue around not being a co-founder with equal footing comes in as you are in an unprotected situation. My 2 cents is just never do it, your are a co-founder or getting paid a fair wage.