cultural differences

"Guinness is blood," a guest informs me at the pub.
I raise an eyebrow, wondering if he's quoting some colloquialism or commercial I haven't seen.
He raises his glass to me and grins. "I don't know how they do in other places, but in Ireland they don't sell the blood. You give it, as a donation. Well, back some time ago they would give you a half-pint of Guinness after you donated your blood."
Now both eyebrows of mine are raised. "A half-pint you say?"
He nods. "They said it restored what you were missin' after the blood was taken. So they would give you a half-pint, and a cup of tea and a biscuit."
My fellow bar-maid is German and tells us that they get paid for giving blood there.
"We donate blood in America too, but they don't give us Guinness," I say, grinning, "Back in college they gave us pizza and a Coke."
We laugh.

I guess in America, Coke is blood.