Why would they have the tare button blocked out? If they did, they’d probably actually be violating the law because they wouldn’t be allowing the customer to tare the weight of the bag before weighing the total. Most customers wouldn’t do that anyway, since they probably don’t know how or care much about the 0.03 lbs that a bag weighs.
As for trying to pull one over on Whole Foods though, you do realize they weigh your coffee when you check out, right? Stick whatever label on it you want, they still know how much it weighs when it gets to the register.
