I can conceivably see the case where someone'd just like to argue "this, very much yes, but not this" - the whole idea that one thing should just then be a "deal-breaker" is more a reflection of the fact that the only substantial way we can then make the argument is through a binary buy-or-don't-buy.

So I don't mind the rhetoric - someone shouldn't have to claim ultimate and eternal loyalty to a product (lest they risk being attacked with a perceived inconsistency pointed out) to argue with and about a product. Of course it makes it no more effective - but it's slightly more truthful.