Recently flew a UX flight (CHS-ORD). FA announced snacks were available for purchase. Offered to no one for purchase as she pushed the drink cart up. When she got to me, she thanked me for 1K and offered me a snack and drink.
Then flew ORD-PHL (mainline). No offer, no service. Just water for the entire flight. And I was in the exit row. I've had them forget many times in the bulkhead seat where I'm usually more proactive.