I know this should probably go to some kind of legal advice subreddit (not sure which one) but, well…
I recently started work at this gas station, and part of onboarding was signing some little thing that basically says that if no one is there to cover me during my lunch that I (in bold) “'voluntarily agree to work an on-duty meal period'”. I do not know if there is ever a plan to actually have such a person to do that, or the exact details as I am new to this and work in general, but I remain curious as to the legality of the whole thing.
It certainly seems dubious, given repeated insistence on lunch breaks from elsewhere.