What about...

Points are recorded for each game: 1 point for showing up to the game, 1 point for each player an individual lasts longer than, 2 bonus points for per place on the final table. 10th + 2, 9th +4, 8th +6 etc..

Example

88 person field, you finish in 1st.

+1 points For playing
+87 points for lasting longer than 87 other people
+ 20 points for final table bonus (1st place = 20 pts)