DSL and dial-tone are completely separate services, that only share a copper line. Verizon doesn't require you to purchase dial-tone in order to get DSL. The only reason I can think of for AT&T to do so is to prop up their telephone business.
AT&T will also sell me naked or dry DSL as it is called. It is sonic that insists on bundling "free" phone service and then charging for it through additional surcharges and fees.
