Mid-2019 while seated in First on a JFK-DFW the FA accidentally spilled a beverage on the passenger next to me and they were given 25,000 miles as an apology. I was in the splash zone (didn't get too much on me) and got 5,000 miles. Neither of us asked for it, so it was a nice surprise when it was offered.
Also December 2021 I was flying JFK-SFO on a paid D1 ticket with a family member. I specifically booked a flight on a 767-400 because I really love the new interior they have. I was upset to find that about 30 minutes prior to boarding there was an equipment change to a much older 767-300 which the interior had certainly seen better days. As far as I could tell from FlightRadar, the plane we were originally taking was parked a few gates down, perhaps some kind of mechanical issue. It was the last flight to SFO that night and I didn't really feel like sleeping in JFK for the next -400 flight out in the morning. I was pretty bummed since it was my travel companion's first time flying D1 and I wanted to make it a memorable experience with the new-ish cabins. Upon landing, I wrote a quick and pretty friendly note to Delta expressing my frustration with such a last minute equipment change. I know it was a silly thing to get annoyed about. Anyway, a few weeks later they wrote back apologizing along with 30,000 miles (15k each) which I appreciated.