Are you Free - No I am not

Often I get to listen to people asking me  "Are you free to discuss or work on important things". I say, no I am not free, but if you think the purpose for which you are inviting me is important, I will come and support you. Yes, when people say are you free, it means it is voluntary work. Any one paying professionally would never use that term, rather they would restrict number of days and use the time efficiently. If I say I am free and would come, a free persons time is not valued, even if I was made to wait for them, because I am free, it does not matter to them.
When I am really free, I would spend time watching a movie, sleeping, etc. Therefore I say, if we want to do something like that together you can ask me - are you free. But are you free is meant for something important and most often where I need to contribute for a real purpose.