If payroll taxes were 100% the responsibility of the employer, and included the employee's income tax obligation. So in the US the taxes are effectively split between the employer and the employee, but in China they're basically all on the employer with a trivial amount charged to the employee.

One of the gotchas if you plan on operating a business in China at all.

Economically speaking, payroll taxes are always a burden on the employee, not on the employer, even if the employer is the one writing the check.

Doesn't that depend on the relative price sensitivity of the employer vs. the employee - namely, the elasticity of labor demand / supply?

That is correct, its just that employees are a lot less inelastic than employers, for multiple practical reasons.

China has those also. They are quite separate (with employee and employer portions, just like in the USA) from what parent was talking about.

You actually get a refund on some of it (retirement) when you leave China.