You stated categorically that wingly doesn't pocket the money
Sorry, but I obviously don't know the detail of the Wingly operation as well as you do: my experience is with Skyuber. If Wingly really are offering "blank cheque" flights for money as I understand you to be implying, then I agree that is wrong and illegal.
The ONLY thing these sites should be offering is the availability of a cost sharing ride on an existing flight. If that is all they do, it is perfectly legitimate; if not, it isn't.