Thanks for the thoughtful response. The argument for propping up the price of labor is that 1) we don't want working people to starve on the streets, 2) politically we've decided it's not the government's job to keep able-bodied workers off the streets. #1 is clearly right, while #2 should be up for debate.

As for wage floors killing jobs, the effect would depend on the height of the floor. Modest increases in the minimum wage have had practically no effect on employment, but I'm sure massive hikes would cause problems.