Using a local password manager, the file could get corrupted or it's not there when I need in in an emergency. Using a remote one, like LastPass, I risk my passwords getting compromised all at once (though maybe not in LastPass' case due to how their architecture works) or, again, not having access to them when I need them.
I have too many machines I'm using for various kind of work where I need different types of passwords. Too many to sync over my passwords and some not even my own, so I don't even want to sync anything there.
Now I have 4 strong passwords I use. One for banking/financial stuff only, one for work, one for "valuable" private accounts bound to my identity (this account here for example) and one for crappy sites I have to give a password to and I don't care if they lose it.
This way I'm not dependent on that password manager being available at a bad time.
The thought of not being able to log into some server people need me fix just because there's no 3g access in the data center or because an update to the password app on the phone didn't re-import the old data correctly is absolutely daunting to me.
Especially because these kind of failures feel more likely to me than one of my more secure passwords leaking out.