References:
Price of wholesale buttermilk pancake batter: https://www.foodservicedirect.com/krusteaz-buttermilk-pancake-mix-25-pound-1-each-74798.html
Average pancake weight: https://www.answers.com/Q/How_much_does_a_pancake_weigh_in_grams So (30 g + 45 g)/2 = 37.5 g
Price of unlimited pancakes as of 2022: https://www.usatoday.com/story/money/food/2022/01/15/ihop-all-you-can-eat-pancakes/6540034001/
Nonsense is a bit of a stretch.
The IHOP exists and is staffed whether or not you are there gorging yourself on pancakes. The rent and staffing is already being spent by IHOP. The factors that can contribute is if the amount of dishes you create make them run the washer an extra time and if the pancakes cool the griddle down enough to increase the cost of heating the griddle. Both of which are negligible.
The only extra cost is the batter itself.
Further reading: https://www.investopedia.com/terms/m/marginalcostofproduction.asp