A Comedy Sketch about 'Your mum'

In the UK, especially amongst young people, it is common to make a insulting joke starting with the phrase: "your mum is so poor she...".

Here is a comedy sketch and transcript about a woman trying to understand this type of joke (warning: it gets a bit rude at the end!):

A: What did Simon mean earlier when he said that thing about my mum and her fingers?

B: Oh that, that was a joke

A: Was it?

B: Yes your mum is so poor when she goes to KFC she licks other people’s fingers. Course it was

A: Oh

B: You know its like saying: your mum is so poor she can’t pay attention

A: Right

B: Or your mum is so poor she…

A: Shops at Sainsbury’s

B: No

A: Tesco

B: No

A: Asda

B: No

A: No But that’s where poor people shop

B: Yes I know it is

A: You told me you can get a can of beans for eight pence in Asda. I wonder if they know about that in Africa

B: You’re missing the point

A: Of course Africans can grow their own beans

B: No the point is not to be so literal. You can’t say your mum is so poor she shops in Asda, because that’s a fact

A: No it isn’t. My mum shops in Waitrose. Although if she’s got the car she goes to….

B: I don’t care where she shops. Look you are supposed to say something that clearly isn’t true.

A: Like

B: Like: your mum is so poor when she kicks cans down the street that’s her moving house and don’t say it isn’t true because I know it isn’t true, but that’s what makes it funny

A: Oh please just do it one more time and I swear I’ll get it

B: Ok Your mum is so poor she buys holes with socks in them

A: Well your mum smells of fish, wets herself and has a fanny like a bucket…was that funny?

B: For different reasons, yes it was

A: Ah, you know what they say, nothing’s so funny as the truth

B: (sigh)

A: What?! Well at least she doesn’t lick other peoples fingers..their faces yes but not their fingers.