Google Chrome mysteriously requests information from Keychain
Google Chrome has the option of saving user credentials to web services. At first login, Chrome asks if credentials should be saved now, saved later, or never saved. Access to the credentials stored by Chrome, and control over these credentials, is found in the Chrome > Preferences > Settings > Show advanced settings... > Passwords and forms > Manage saved passwords link.

Unusual web service login requests that occur on application launch, or at odd times during a browsing session, can sometimes be traced to Chrome saved credentials. When these credentials also involve the user keychain, I suggest that the credentials be deleted from both the Chrome saved passwords list as well as from any associated keychain entries. There may be multiple  keychain entries, too, which should be deleted.

Furthermore, if you sign into your Google account in Chrome to take advantage of the syncing functions, (which can be quite useful,) you have the option of saving and syncing passwords along with other elements. Depending on your level of paranoia, you may want to shut this down or never sign into your Google account.

Personally, I never save any credentials to financial or medical sites, nor do I save credentials to my school's file servers and web services.