grammar and fiction

One day I was out with everyone from my Extreme Birding Club. In this club we not only spot the birds, but we capture them and make them tell us a secret. The more rare the bird, the more rare the secret. As everyone knows, at least where I live, birds are stubborn about revealing secrets. They know a lot of them. I won’t say we’re above pulling out a feather or two in order to get the bird to spill. Still, we don’t kill them. We don’t eat them. You could say it’s kinder than buying a chicken at the grocery store and pretending it just appeared there out of thin air. You buy the chicken. You’re part of the chain of events that causes the chicken to be born for his solitary purpose of being consumed by humans You eat the chicken bought from the store. Me, too. I’m not criticizing—just saying. Don’t judge me.
Extreme Birding isn’t for the faint of heart.
After we get our secret we always give the birds some food and send them on their way.

Extreme Birding will make you thirsty and so the group often goes out for a beer. While having a drink someone said, “I just called my wife and told her ‘the whole group of birders drink Shiner Bock' and she corrected me and said it should be ‘the whole group of birders drinks Shiner Bock.’ Who is right?”

I decided to give the Grammar Guru a call right then and there. It turned out he was in the middle of chanting. Gurus chant a lot.

“What were you chanting?”
“Old Marx brothers quotes.”
“What’s one?”
“Outside of a dog a man’s best friend is a book. Inside of a dog it’s too dark to read.”
“Good one.”
“What is your question grasshopper?”
“I wish you wouldn’t call me that.”
“Another Marx brother quote is ‘wishes are like buttocks. Everyone has one.”
“That’s not a Marx brothers quote.”
“Ask your question.”
I asked: Is it “the whole group of birders drink” OR “the whole group of birders drinks.”

“Ah, he said, "Group noun problem. A group is considered singular. It’s like a class or a flock or a committee. If it is considered one, it’s singular. What’s confusing here is that the writer added the “of birders’ which made the writer think the subject was birders (plural) which would mean the noun would have no “s” on it. (They drink/ It drinks). However, since the subject is group, it’s singular (it drinks) so the sentence should be ‘the whole group of birders drinks.’”

Here are more examples:
The class learns.
The class of students learns.
The flock flies overhead.
The flock of birds flies overhead.
END OF STORY.