Jim Logajan wrote:
It seems goodwill is considered compensation.

Goodwill per NTSB always means a business context, such as
expectation of possible future $$ benefit. The two cases you
cited have complicating facts. In Murray, the pvt pilot had done
subcontract work for the tavern owner who threw on the Super
Bowl party deal which included Part 135 transport of the pax to
the party site. In both cases, the pilot showed up as a
substitute for a prearranged Part 135 flight where the charter
aircraft or 135 pilot was OTS. The pax likely assumed the
substitute guy was a commercial operation also.

I'm alluding only to a pure (and rather common) case of a favor
to a friend/relative, no business context, the pax know who you
are as not comm'l/charter, and the only "compensation" is your
logging time in your own airplane at your own expense.

Fred F.