The IRS might need the address only to contact you, BUT some states are aggressively looking for additional revenue. Be aware that some states are now going over federal returns looking for people with mailing addresses in their state who didn't file as a resident. With no other supporting data they are then sending out demand letters saying "we think you are a resident so refile your taxes and pay us $X plus interest and fees." I would highly avoid using any mailing address that isn't in the same state or country as your residence.
