Its not someone might abuse it. Its a ton of people will abuse it, raising costs for everyone.
Heres a similar example. I dont know if Bernies everything is covered includes this (I hope not!), but lets say it included coverage for alternative medicine. Theres nothing to discourage this; its free! Say that, because of this, 10% of spending ends up going to shit that doesnt work. This benefits nobody; in fact, it hurts people because theyre putting off real treatment. And everybody pays more because of it! The same can occur even for procedures/meds with some merit.
Now if you have copays/deductibles, theres incentive not to do this. And on average, everybody is now paying less because it cuts down on unnecessary spending. And Im not saying that copays/deductibles need to be nearly as large as they are now, or that they cant, e.g., scale with income or something. They serve an actual purpose in helping to correctly align incentives.
That's why you need the other half of socialized healthcare - a single payer that controls what is paid for and what is not.
Or as Sarah Palin would call it, a death panel.
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September 1, 2003; November 4, 2007; September 2, 2013 Congratulations to DP Oblivion in the Guru Contest!