Another small consumer victory

Menu in Burger King reads:

Small Fries: £1.25
Regular Fries: £1.45
Large Fries: £1.65
Extra large Fries: £1.85

Me: (in burger king at waverly station) Can I have small fries please.
Burger King employee: Yep! (Goes to get fries. I hand him £1.25) You're 20p short, it’s £1.45.
Me: No, sorry, I wanted small fries at £1.25
BK: Small fries are for children. I’ve given you Regular fries, which are small fries for Adults.
Me: thanks, but I’d rather have small fries.
BK: But you can’t. They are for children only.
Me: Why? It doesn’t say that on the menu.
BK: No, but that is the rule.
Me: But what difference does it make? I want small fries, as offered on the menu.
BK: But I’ve rung Regular fries into the till now.
Me: But I didn’t request Regular fries. I’ve given you £1.25. I would like small fries please. (look at him straight in the eyes.)
BK: (huffs, tries to stare me out – gives up) Oh all right then.

It’s only a small moral victory, but it felt GOOD.