If the law says prices should be listed then they should be listed on everything forsale privite forum or not.
That is not the letter of the law. It is the law that they have to be listed in store. However a forum is just that. Now if it is a website where you can actually click to purchase that is different. This is more of a 'showcase' for vendors to list what is available. I agree it would be nice but having experience on both sides of the fence can understand why vendors sometimes choose not to list price as competition is already fierce enough and its easy enough to just contact and inquire.