I believe I saw an article where 20 celebs vowed to leave.

So, twenty participants (or 40 or 60 participants). Each ponies up 5 chips. If your appointed celeb leaves the country, you win. Hopefully there would be more than one winner. The added attraction to this contest is that you can try and contact your celeb and remind them of their promise

Now if Cher actual flys to Jupiter (the planet, not Florida) as promised, that contestant wins all chips and 100 chips from me.