It doesn't seem preposterous to me at all. If the goal is to show the price breakdown on marketing materials, it's going to be tough for AT&T to fit 29,000 diff

It doesn't seem preposterous to me at all. If the goal is to show the price breakdown on marketing materials, it's going to be tough for AT&T to fit 29,000 different permutations of tax regimes in a banner ad. "the company “would have to create over 29,000 separate labels”" from your source 2.