The relative value of someone who is usually the butt of jokes. Usually the shop/office whipping boy/girl. i.e. someone who is gullible, a rumor monger, gets angry easily, is easily startled etc.
Dominic is such a dweeb, but he's very gullible so he has a high entertainment value.
Entertainment value. You have your wages, holiday pay, vacation and benefits. Then you have the entertainment value. Often worth more on a day to day basis than all the rest of the compensation from work. It's sometimes the only way to get to the end of the day.
Chuck: "Hey Bob, how's it going today?"
Bob: "This place is run by idiots. I can't take it any more."
Chuck: "Well Bob, you can always look for the entertainment value!"