Earlier quoted context omitted.
That leaving is an option is what the parent comment is saying ("refusal to work at the proposed price"). The drivers in the article are refusing to drive at the non-surge price, and when the price surges, they find the price acceptable and so take the rides. The part of parent comment that you quoted is just about how the take-it-or-leave-it nature leaves no middle ground (bidding).
But that is false. Acceptance or refusal of an offer is bidding. It's essentially an auction: Lyft/Uber asks, "Does anyone want to sell at $X? No? OK, how about $X+1?" etc. What the drivers are doing is not bidding, it is colluding to hide the true market price, i.e. what the lowest bidder would actually be willing to accept. That is illegal. Please note that my sympathies are very much with the drivers. Their situat…
Breaking the law is exactly what Uber and Lyft did and now that they're on the other side they're whining about it.