Why? #1... its got a catchy name that gets people's attention. #2... Its easy to learn (2 minutes), #3... requires little to NO SKILL, $4... gambling is involved (people love to win money), and last... its easy enough to play for those "under the influence".
Complicated board games get to be too much especially with a lot of people and drinking may be involved. Too many for card games like Spades (made for 4 people) and Poker / Texas Holdem can require too much money, and too intimidating for the beginner to learn and feel comfortable playing.
So why is it called SCREW YOUR NEIGHBOR? Buy my gig and learn to play... I'm sure this game will be a hit!