For services where a user can only access their own account, I mostly agree. But sometimes one users' bad security practices can compromise other people's security, too. If you're sharing confidential data with other people - for example, via SpiderOak[0] - and any one of those people's accounts are "hacked," it doesn't matter how good your password is.

[0] I'd say Dropbox, but you shouldn't be putting confidential data in Dropbox.