You're making the assumption that battery packs are going to be...

You're making the assumption that battery packs are going to be hugely expensive when- or if- they come up for replacement.

It's not something I'm particularly bothered by. In ten years time batteries will be much, much cheaper than what they are now.

Now if you don't want one, fine. Don't get one. But don't assume your case is the same as mine.