Well, they can always refuse service, but now their refusal is linked specifically to the crossed-out lines, an action that can lead to various paths. If the deleted lines are known by them to be overreaching, they are economically better off to provide service and earn revenue, instead of losing 100% of revenue and appointment slot to a minor technicality worth much less.
the way it works with a contract, you can always choose to remove clauses - but the other party has to agree to it too. they might acquiesce if for example, they think denying you service might actually lead to a lawsuit that would point out their illegal behaviour.
I’m actually fully on-board with everything in this thread. This should obviously be taken more seriously than it is.