I'm fine with these people receiving preventative care, but they should share in the cost, rather than the taxpayer having to pay for all their health care.

40% of Californians are on Medi-Cal. 30 to 40% of Californians don't pay income taxes. The overlap between those two groups is basically 1:1. Therefore, 40% of Californians are essentially freeloading on the healthcare system through a combination of receiving care they don't pay for or via insurance they don't pay for.