BAM! (Mr. Willie)

My name is Willie - Mr. Willie
And what I do is when peoples come in
I GREET THEM!

And I tell them how they doin
I will ask them how the kids doin
Most the time they come up
And they want a bam

What's a bam?

BAM! That's a bam
BAM! That's another bam
And what I do, and what I do
What's the word for it?