It is accepted voluntarily by employers who can choose to go into business or not.
the fence riding is hilarious.
Fence riding? I run a small business and, while I do not currently have employees, I have had employees in the fairly recent past. I chose to hire those employees because a) it would benefit me and b) they needed the work. I could as easily have chosen not to hire those employees as that would not have significantly reduced my net income. When I hired them I knew full well that I would be required to pay general liability insurance based on their earnings, I would be required to pay work comp premiums based on their earnings, and I would be required to pay FUTA and SUTA insurance based on their earnings.
I chose to do that. Again I could have easily chosen not to do that as well as choose not to run my own business at all. There were jobs that paid as well available to me and somebody else could have enjoyed all the headaches of being in business.
I chose to do that because I like being my own boss. That is a privilege I do not take lightly. And I accept the responsibilities that come with it.
There's no fence sitting here.