In the USA it is normal to tip at least 15% if the service is fine and 18-20% for good service, even more if it is fantastic. Sorry but if you can't afford to add at least 15% on top of the meal price, don't go to those places.
Unless the restaurant advertises that they don't accept tips as they offer a significantly higher wage, you should follow the norms and tip.
If you can't afford to use the premium dining plan AND tip, then choose a plan that involves less table service dining.
(I agree that the American wage system is messed up, but you choosing not to tip won't do anything to help fix it, its up to restaurateurs and law-makers to change the system).
Oh and this Facebook group you mention sound like a right bunch of selfish cheapskates.