I've seen a lot of people asking WHY this was something they'd get in
trouble for, and I think I have an answer. First, from Mike Weller's
post:

Put it into the context of when and where it happened.

They shut off the engine on the runway, the prop stopped, and then
they rolled at least a another quarter of a mile after making a 45
degree turn off the runway, rolled down the taxiway, and the made
another quick turn and stop to get to the gas pumps.

Take a look at the distance involved. To coast from the runway, around
that corner and all the way to the pump, they spent most of the taxi at
well above brisk walking speeds. Unsafe taxiing speeds can do a lot of
damage and pose a risk to anyone walking around there, especially with
the engine off.

Additionally, if they taxi past a bunch of planes and lose a tire at 40
mph or so, how well do you think they'll be able to avoid smacking into
the parked aircraft?

So, in summary: They were taxiing way too fast.

Ben Hallert
PP-ASEL