After a small scuffle with Mrs. Salt over the existence of Loompaland (the Oompa-Loompas' home country), Willy Wonka begins to tell the story of how he found them.
Loompaland is a terrible place because of the snozzwangers and whangdoodles (stick with us for a second, you'll get used to it). In any case, they were terrorized by terrible beasts and they had nothing to eat.
All the Oompa-Loompas wanted to eat was the cacao bean, which, Wonka explains, is what chocolate is made of (this part is true in non-Dahl world, too).
So Wonka brokered a deal with them: if they would come back and work for him, they could have all the chocolate they wanted.
And voila! Here they are, he says. They love to dance and sing and are a little mischievous and...
Veruca wants one. Surprise, surprise. Her dad says he'll get her one, but before they can finish the discussion, Mrs. Gloop starts shouting to her son, who has sneaked off to the river and is gulping down chocolate like nobody's business.