Bagels.

B: We should get a bagel cutter.

Me: What? Why? What a waste! 

B: Oh sure. Just because it's ME who likes bagels...

Me: You can't cut a bagel?

B: I'm sensing a dislike for bagels. Because I'M the one in the relationship who likes bagels...

Me: ok, we can get a bagel cutter.

B: Oh really? I don't actually want a bagel cutter. A knife's perfectly fine.