This is by design. Cellphone companies intentionally make their bills so confusing that you don't know what you're paying for. Which is why your $69.99 plan ends up costing $86.73 every month. And, sure, if you click that link you'll discover that AT&T eventually got sued for that s**t, but don't worry: Phone companies figured out other ways to lie to us. Like that time Verizon intentionally overcharged all their customers for years, and no one cared. Or that time the government gave them $2.1 billion in tax breaks to install fiber optics in Pennsylvania, and they didn't do it. What was their excuse? Haha, it's adorable that you think they bothered to offer an excuse.
Why This Will Never Change
Getting mad is hard. Reading fine print is also hard. And the whole reason we have cellphones and internet service in the first place is convenience, so putting effort into improving the experience would be, ya know, paradoxical. So instead, we just shake our fists at the heavens and mutter, "Ahh, they got me!" every time we read our bill. "Can you believe this s**t?" we ask, perhaps. Or, in extreme cases, all we can muster is a long, raspy, "Ehhhhhhhhhhh ..."