The ones that track your identity are sort of a big deal. There's no reason to keep this litter hanging around.

You've got it completely backwards. Invert your questions: What cookies shouldn't be deleted, and why shouldn't they be deleted? The continued existence of a cookie requires justification, not the deletion of a cookie. Only a small minority of cookies exist for the users' benefit.

Disable it then, just because you're apathetic to such matters doesn't mean the application should assume everybody is.

>inconvenience

It's seriously doubtful you or any other user will notice any negative ramifications from third party cookies being deleted, because there basically are none.

Well, it certainly seems like you care, so which is it? Do you care or not care?

Apathetic to cookies or being tracked, care about free services. Not really complicated.

then they should show ads without all the tracking...