Ants can be a major issue, they can get into our homes and businesses. They can find their way into food storage and pantries and spoil food. I have even seen them in refrigerators, stoves and microwaves. They can also get into restaurants, this can cost the restaurant business revenue and lost of patrons. Pest control is essential for business that rely on patrons and also that serve food or beverages. There are a number of species that can get inside homes including nuisance Pharaoh, Ghost and even Carpenter ants will trail to sweet or protein foods. It is really important to understand the habits of the nuisance critter you are dealing with, in this way you know when they need protein and/or sweets as carbs.
Some great information from the National Pest Management Association