I've always wondered whether it is appropriate, as a customer, to send a thank-you or otherwise note something very helpful that an employee has done which they "are not supposed to do"
Example: last week, I was flying UA DEN-EWR. I got to the airport a few hours early, and they put me on a DEN-LGA flight. The gate agent said he wasn't supposed to put me on the earlier flight since the cities aren't coterminal any more for that purpose.
If I were to send in something, would that get such an agent in trouble.
Per an above post, many things which employees do are part of the job.
When they go above the call of duty, I think it's appropriate to thank them -- unless it gets them into trouble.