Prepare Graham Cracker Crust:
1. Preheat oven to 375 F.
2. Blend graham cracker crumbs, sugar and butter.
3. Measure 11 1/2 ounce portions of graham cracker mixture into each of 3 12x10x2 inch half steamtable pans. Press down firmly, covering the bottom of each pan.
4. Bake for 8 minutes. Cool completely
5. Pour cold eggnog and milk into mixer bowl.
6. Add cheesecake filling. Mix on medium speed 1 minute.
7. Scrape down sides and bottom of mixer bowl. Mix on medium speed 2 additional minutes.
8. Pour 3.33 pounds of filling into each crust-lined pan.
9. Chill at least 1 hour before serving.
10. Cut each pan 4x4 for 16, 3x2 inch squares per pan.
11. Dollop each serving with whipped topping, if desired.