Liberals don't want to destroy private enterprise. They just want to make private enterprise "better".

To liberals, one drawback of Wal-mart is that its ruthless drive for efficiency is a bad thing:

And because Wal-Mart so obsessively pursues the lowest possible prices, they're not only depriving their own workers of generous benefits and compensation, they're making it literally impossible for their producers to do so, as Wal-Mart won't abide by the minor cost differences that on-shore production and respectable benefits demand.

On the other hand, one of the big selling points of national single-payer health care for liberals is that it will efficiently keep prices down:

I would suggest an alternative hypothesis -- the vast majority of the public has no idea how inefficient the U.S. health care system is relative to the systems elsewhere in the world. I have been reading the NYT almost every day for more than 30 years; this is one of the few times I can recall any mention of the relative inefficiency of the U.S. health care system. On the rare occasions when the NYT talks about the health care system in another wealthy country (e.g. Canada, Sweden, England), the article is usually focused on the system's problems, and generally implies that its demise is imminent. I would be very surprised if even 10 percent of the NYT's readers knew that per person health care expenses in the U.S. are more than 60 percent higher than in Canada and more than twice as high as in England, and that both countries enjoy longer life expectanies.

In other words: Wal-mart is evil, so let's make the federal government more like Wal-mart!