I was called to treat a house for ants today. In walking up to the front door of the house, I saw five trails of ants within a 10-linear foot section of the home. And there was no more than 1/8th of an inch between each insect - it looked like the house was bleeding through black capillaries. I could tell by looking at this part of the house that it was a front bedroom, and not a kitchen area.
I knew even before ringing the doorbell that it was very unlikely these ants were coming inside for food. It's much more likely, if they're going into a bedroom from the outside, that these were "exit trails" of ants going outside to find their food and taking it back to a nest inside the home.
This isn't what most homeowners would assume when finding ant trails outside their house. But knowing that we've had lots of rainfall recently in Kansas City, and the ground is really saturated, I knew that this was just the kind of push these ants needed to take Stevie Wonder's advice and reach for higher ground.