Thanks for the info. I was about to go insane myself. I've got every achievement except this one, and I figured for sure that by the time I got to 10 hours--or at worst, when I got to 40,000 in the food bank--I'd have dined on my thousandth shark.
Idea for the sequel (as if the game programmers actually read these comments and say, "Wow, that IS a good idea!"): put a counter in the menu somewhere if you're gonna make us eat a thousand sharks, or play for 10 hours, or any other mundane time-consuming journey.