There you said it...you just compared the Ipad pro to the Macbook pro. Why did you do that? Because they almost cost the same. Am I right?
It's like...OK here you can buy this really expensive bike...but for a little more you can have a car.
Yeah, but buying a car is so 1999. I live in the center of Amsterdam, work in the center of Amsterdam and have all my social contacts in the center of Amsterdam, so why buy a car? You'll never be able to park it, some dumbass will key-scratch it, costs the world and you can't transport the kids. So you spend a fortune on a cargo bike with electric drive which holds your kids, groceries and everything else. The bike costs even more than a cheap second hand car, but is way more practical for my use.
Try this with a MacBook Pro: it's lighter, I can make it even lighter without keyboard, I can write on it, it has 4 speakers, it has LTE, I can touch to navigate...
Now show me how that on a MacBook Pro?!
I don't care about the price, I care about the tool I have with me and how it works for me. If it doesn't work for you, try something else and be happy with it.
Edit: the cases are expensive beyond any reason. But there you have the choice of buying 3th party. And I bought all of them from Apple on the first day they were available. So what do I use? I never use the Smart Cover, I gave away the smart case and I always use the Smart Keyboard and Pencil. I like both of them really a lot. So much I bought a spare Pencil, just to be sure I have one when I break/loose it.