No, that's the best interpretation of the policy, but it's not what they're doing: apparently they're only charging $2/month if you don't call enough for AT&T's taste.
Let's think about it this way. AT&T is now charging $2 a month to have landline service. They will waive the fee for customers who use more than $2 a month in long distance charges.
It's not a customer friendly policy, as it just serves to squeeze $2 from customers who aren't using more services. But it's not criminal to add a service fee(as much as I hate it as well).
What difference does that make? How is that not strictly better than charging $2/mo no matter what? And thus if raising rates by $2/mo isn't "criminal", how could this be?
The thing about this is that it's somewhat dishonest. They have an advertised price, but then there's an additional fee if you don't buy additional services. It's like going into a store and buying a box of pasta for $2, and then getting charged $3 because you didn't buy some sauce along with it. Sure there was fine print beside the price saying that's the price when bought with sauce, and otherwise a $1 non-sauce-usage fee applies, but the reality is that they're counting on people to not read their bills too carefully.
You could look at it as they're charging everybody $2 a month, but offering a $2 a month credit to their best and most active customers. Looked at like that it doesn't sound to bad at all.