I didn't want a way to research and ask waze a free parking place (because that'll be a carnage for sure, I totally agree).
But just have the possibility to see free spot on the map (like cops or roadworks).
You leave your parking place, you tell waze and everyone driving arround will see a popup "parking".
No research function or whatever
For the moment, I use the "chat function" but i don't know if this is efficient.