Over the last six months, I've gotten towels on the vast majority of flights to the mainland ex-HNL.

We never get them SEA-HNL, and I didn't get them either way SEA-OGG-KOA.

The first time they materialized in at least a year, the flight attendant was equally surprised and said that she thought it was a mistake. But it's been pretty consistent since then.

Kind of interesting -- we get a chocolate chip cookie out of Seattle, and a hot towel out of honolulu. Personally, I prefer the towel.