How many pair of speakers do you own?

To answer your second question, none of your suggested answers applies.

In my case, (1) when I upgrade, I don't get rid of the old equipment -- they usually just get reallocated to other rooms; and (2) I think it's nice to be able to listen to good music reproduction in different rooms especially when it is also consistent with the decor. Do you have children? Are they into music? Should they have their own stereos, too?

Of my 8 pairs + 1, 2 pairs + 1 center channel are in my main system, which is both my best stereo and home theater system, and 4 pairs are in stereo systems in other rooms. (2 pairs are in storage.)

1) 1 pair Cain Abby (main speakers)
2) 2 Mission 731i, 70C, Sony Surrounds ("Home theater")
3) Tivoli Model One
4) maybe a pair of Quad ELS57

Total 8-10 speakers sitting around.

why you would own more than 2 pairs of speakers

More than one place to live - nonlocal entanglement.

You have no idea how useful this thread, but just one question first, where on earth do you keep them? To answer the question, I have 1 pair only, obviously not a serious audiophile then. My wife insists I am being extravagant when I bought some Acoustic Zen Adagios recently(and sold my Living Voice Avatars). When she next criticises me, I can wave the print out of this thread at her and prove how frugal I am. Seriously, I would have nowhere to keep more than 1 pair.

Counting subwoofers, a total of 20 speakers. And I just sold 2 pairs. When you have 2 home theaters and a couple of stereo systems, it adds up. Luckily most of them are small.