default gateway = localhost ?!

so at work we just got these sbc dial up accounts to use while we are on the road, and they dial into an 800 number. but once your connected the default gateway is the same IP address as the local host. and the routing table show essentaily.Network Destination Netmask Gateway
how is this possiable? is the trafic that is being directed back to the local host being picked up by some sbc program and directed to the right destination? why on earth would they do this?

For any point to point connection, such as a dialup using PPP(Point to Point Protocol), the default gateway is meaningless. Various implementations will put different things there, but whatever they put there doesn't matter.

When you send anything on your PPP interface, it goes to the other "point" anyways, where it is routed by that box.