You can carry passengers on a PPL, so long as they don't pay you or anybody else for the flight.
That's the UK position.
There is a bit of a grey area where the payment is made to an apparently unrelated 3rd party and this arrangement has been probed by quite a few outfits - even in the UK - but it is a non starter anywhere I know about. In the UK you need an AOC to do pleasure flights.
Variations on the theme include getting them to pay for something else not related to flying but again a non-starter over here.
My understanding on a PPL was you could hire out an a/c yourself and carry the passengers for free or IIRC they could make a "contribution" towards the costs of the flight and nothing more, providing you yourself paid the same amount towards those costs.
You can do cost sharing but then you are very limited on how the flight is advertised. Again, some grey areas in there, but basically the cost sharing limits mean it will never make anybody any money.