I know. I once had a client insist on a written guarantee being issued AFTER completion of work. I told him "I can absolutely guarantee that the structure in question will NOT grow back overnight." He released me from that requirement.
Some GC's I have worked for in the past will release my retainage upon completion of my scope, so that's a plus.
We're kind of the redheaded stepchild of the construction industry.

Nuke is right, it is primarily in place to keep the "fly by nighters" from doing shoddy work. This is not a standard P&P bond. It isn't linked to either performance of work or payment of subs, it is to further insure against damage to city property. I agree with blast that it is somewhat redundant, especially when you can simply add the city as an additional insured. It is simply part of the price of doing business in my fair city.