Why is coffee used in some chili recipes?

[Krystal]

I wish to cook it for my family but am concerned about the "caffiene" content for young children. Why is coffee used? And will it matter if I removed it? Is there something I can substitute it for?

Here's the link to the recipe I wished to use: http://www.foodnetwork.com/recipes/dan-smith-and-steve-mcdonagh/all-day-pork-loin-chili-recipe/index.html