Why do so many people assume that anyone that needs any sort of public assistance is lazy?

I work my *** off and live on a minimum wage salary. I have Crohn's Disease and Social Phobia, so even if I was making lots of money and wanted to pay for my own health insurance, none would except me due to preexisting conditions. I am on state insurance, which helps out a lot. I refuse to go on any other state assistance, because (even though I qualify) it simply isn't necessary. I get by with what I have. The only thing I *need* is state insurance. And yet I get scoffs and "that's tax payer's money", as if *I* don't pay taxes. As if *I'm* not a taxpayer, and as if *I'm* lazy and sit on my *** all day and feed off the government. As if *I* don't deserve to be covered. People can call the police if their neighbors are being a bit too noisy, and not have to pay a dime or deal with scoffing, but if someone has a health problem and can't afford to pay the thousands of dollars to fix it or keep it at bay, then they should rot. Why do people think like this?