In the US, it's a cash vs benefits trade-off. I am happy to sacrifice a lot of salary to get the Cadillac healthcare my company offers to me and my family at no cost.
It's like buying an insurance where number of years it covers depends on how many years you want to work for a company. Yes, that means getting little sicks is not that worth it. Having serious condition? It's a fucked up anyway.
Why not just buying the healthcare package yourself and paying for it from more cash you make as a contractor? Honest question since I live in a country with a very different healthcare system...