I think the best way for you to be convinced (although at this point I doubt it's possible) is to just Youtube the Fire, the Galaxy Tab, The XOOM, and the Transformer Prime. Find videos that show navigation, UI elements, etc. If you can't see the differences between the Fire and the other tablets, and the similarities between the other ones, then there's no point in arguing with me, because I won't be able to convince you.
I've used all of them myself, and as I told you, they all have different skins, but they also all run the same OS underneath. The HTC Flyer and Motorola XOOM are completely different when you use them, but they're still both Android.