When creating/editing conditions via the module (AMM), the Pro only conditions are disabled.
When creating/editing conditions via the Conditions component, all conditions are available, as you might be creating this for something else than AMM. For instance, if you have the Pro version of ReReplacer installed.
PS: You could create a condition using 'Pro only' stuff, and then assign it to a module in the free version AMM.
All the Pro only conditions will however be ignored on the frontend.