Years ago I used to work in a record store in a mall.
The city would sell chamber of commerce gift certificates that were accepted at almost every store in this city and literally every store in the mall, except mine. When people would try and use them we explain that we do not accept them. Most people were cool about it, some kind of annoyed, and honestly I understood their annoyance.
This one day, during the holidays, when we had seasonal help, this lady tried to buy some stuff with these gift certificates. I go into my speech "unfortunately, blah blah blah".
She wasn't having it. She starts getting angrier and angrier and says "they told me these can be used here".
This girl who had been seasonal help for years overhears this lady and comes over and has the lady explain what is going on. The angry lady repeats it all and ends with "they said I could use these here".
The seasonal help girl says "they didn't tell you that".
And the lady says "how would you know that?!".
My co-worker then says "because I work full time at the chamber and I sold you that gift certificate".
The lady's face turns bright red and then she says "oh" and then leaves super quick.
I mean, we had to put her stuff back, but it was worth it.