The FA's get a few laughs each time. It gets old fast, especially if you're with them for 3 segments that day. It's become a right of passage with Southewst--similar to the first time I flew Southewst (last C to board, first time I heard x joke.) I've just learned to tone things out when needed.
The FA's most exciting part of their day may be to make a couple people chuckle while they try to lighten the mood of the flight. They don't have a menial job, but it is repetitive. As a business traveller I'm glad that their employer lets them have a bit of fun in flight.