In my case, it depends on who answers the phone and takes the order. There's an Applebee's across the street from the hotel I've been staying at M-F for the past six months. I normally order from there once a week, sometimes twice, and they normally only have one person who runs the carside service. I normally tip 10% up to the next whole dollar, but there's one server who continues to try to add tax to my take-out order....so after reminding her for about the fourth time, I've decided that she must not listen very well. She no longer gets a tip.
And no, I'm not waiting until I get there to remind her about the tax -- when she confirms the amount before I hang up, I've reminded her that take-out (in Ohio at least) isn't subject to tax, and she says "oh yeah, I'll take it off." Funny that it's never once come off the tab she brings out to the car.