I noticed this a long ago, but I wondered if anybody else cares at all (or has noticed). If you have G-mail and are logged in, the company associates any searches you do through GoogleMaps (along with other services, I'd suspect) with your account. It will memorise all of the addresses that you've searched for when planning a roadtrip.
So, that leaves me with these questions:
1. Does anyone care?
2. Is there any way to "erase" this history from the account?
P.S. Does Yahoo also do this too?