Flytenow, Uber of the Sky

[Carruthers]

In the UK, sharing flight costs is deemed to be 'flying for hire or reward' and therefore beyond the privileges of the private pilot's licence. As such it leaves the pilot liable to prosecution.
I'm not up to date with the current state of affairs, but know that it always went on 'informally', shall we say.
I don't suppose that it ever occurred to the participants in such an arrangement as to where they would be left in the event of an accident, eg invalidated insurance and the possibility of financial ruin.
The practice may well have been cracked down upon in recent years on pain of even greater legal penalties.
I'm surprised at the situation in the US being any different until now.