We would all like to fly when someone else is paying and most people do not want to bother with a CPL, but thats life for the PPL, You want to fly You must pay ,I think is it very simple to understand and I am not a lawyer,
I and my friends go to Europe a fair bit from Belfast, usually 4 up in the TB20, if we fly EGAA - LFRD - LFMP - EGJJ - EGAA, that is about 11 hours in the TB. All 4 pilots will fly a sector and all will have a different flight time but we divide the total cost by 4 and that is legal.
I have flown "for free" at both gliding & para dropping clubs, with the belssing of the CAA, but I think you will find that when it comes to transporting yourself and friends around the CAA will want you to pay your share of the flight.
Tony