Thermodynamics, You Take It From Here, Part 8

I work for a chain bar and restaurant that gives free refill coffee when you purchase your first cup. Today, whilst serving, I have a woman order a coffee. I know she is going to be trouble; she orders her drink whilst I’m standing in front of her pouring a pint for another customer whilst two more are waiting patiently. The foot starts tapping, and then the huffing and harumphing start.

As I pass over her cup, so she can finally get her coffee:

Customer: “This cup is cold; it should be hot.”

Me: “Sorry, all our cups are cold unless they’ve just come out of the wash.”

Customer: “I always have a hot mug; my coffee will go cold.”

We don’t have a limit on how many refills you get on your coffee or what sort of hot drink you choose, including hot water for tea.

Me: “You could put some hot water in it first to warm it up if you wish.”

Customer: “It’s common sense to serve coffee in a hot mug.”

So, I’m meant to keep all my mugs hot, just for her? Does she keep her mugs hot at home, ready for when she wants a brew? Or is she like everyone else (with common sense) who uses a cold cup and drinks it quick enough for it not to go cold in the first place?

Related:
Thermodynamics, You Take It From Here, Part 7
Thermodynamics, You Take It From Here, Part 6
Thermodynamics, You Take It From Here, Part 5
Thermodynamics, You Take It From Here, Part 4
Thermodynamics, You Take It From Here, Part 3