Some states are aggressively looking for additional revenue. While you are given a choice in TurboTax to supply a mailing address and TurboTax says it doesn't have to be your residence... some states are now going over federal returns looking for people with mailing addresses in their state. With no other supporting data they are then sending out letters saying "we think you are a resident so refile your taxes and pay us $X plus interest and fees."
