They provide it because they have to

no, they don't have to. they provide coverage to recruit / retain employees, or because they feel like its the right thing to do.

Although I really have no idea what you mean by 'the market'.

supply and demand.

Just because 'the market' demands it, does not mean it is good.

so?

I believe that corporations would not offer health care if it wasn't expected of them by society or 'the market'

in other words, corporations provide health insurance because the market demands it. glad we're in agreement.