Why lie?

I met this person last week and while this isn't the conversation that we had, it is definitely in the spirit.

Me: What've you been up to?

Guy: I was on HBO.

Me: Really? What?

Guy: That Jim Norton show.

Me: Huh. I saw all of those. What episode were you on, I must have missed it?

Guy: Yeah, well, I got cut out, but I still got paid and they'll probably use it in an episode later on.

Clearly this guy is lying. I had just met this him but he knew my friend that I was with. What gets me is, all three of us, my friend, myself and the guy, knew these were lies, yet he wanted to keep putting them out there.

Seriously, what is the end game for these people? If I don't know you, there's no reason to lie to me. If my friend knows you already, there's no need to impress him. If everyone involved is a comic, you're not going to pull one over on us like that. So, what's the point?

There are times that I'd really love to see inside someone's mind just to see where they think it all leads.