Ok this I never understood. Why would business SDSL at a slower speed be more expensive than ADSL at a faster speed?

At verizon.com, they advertise business DSL with speeds of 1.5M/384K with a dynamic IP for $39 a month plus setup fees etc. Now they also advertise SDSL with speeds of 384K/384K with a dynamic IP for $80 a month! The only difference is that the SDSL comes with 20M of webspace and unlimited remote-dial up access.

But still, why would it be so much more for SDSL?? I mean, you're paying more to get a slower download speed...?