Just the other day I asked if someone would come in on their day off from work in order to cover for me. I paid them, and they performed the service. All this went down without any government intervention, coercion, or use of force.

I see a dilemma here.

1. If I think of your transaction in isolation, it's free but not a market: it's a bargaining problem.

2. If I think of your transaction as part of the broader labour market, it's not really free; it's influenced by government regulations & macroeconomic policies, if only through their effects on the general price level, the general wage level, and the supply & demand for labour.

I reckon your transaction is an example of what mtraven's talking about rather than a counterexample!