Actually, that's not true
In many areas, you can get what is called "naked DSL". AT&T does not promote this since they want to sell you a package. (This was part of the deal they made with regulators to get approval for one of their mergers years ago) Althought they are required to provide this service, they do not promote it, and actually go out of their way in letting people know it exists. (there is no permalink on their web site as they keep moving it)
If you Google "naked DSL" you should be able to find the information you need.