I imagine there will be some grousing about this among users, complaining that Apple is increasingly "nickel-and-diming" us, removing default components and charging extra for them.
But let's be fair. Apple has gone both ways. For example, an AirPort Extreme card and Bluetooth support are both standard with laptops, even though they were optional when they first arrived on the scene.
In the case of the remote control, I suspect Apple simply made a decision based on cost vs. use. That is, if the vast majority of people who purchase a Mac laptop never or rarely use the remote control, then Apple is wasting money by providing it to people who will just let it sit in a drawer. Plus, there are the people (such as myself) who now have several of these remotes (after purchasing laptops, an iMac, and an Apple TV over the past few years) and who don't need a new one with each new purchase.
So...make it an option for those who want it and save money (by not raising the price of the laptop) for those who don't. Compared to the status quo (keeping the remote standard while not increasing the price), an optional remote can save Apple a significant amount of cash. Let's suppose (and I am making a wild guess here) that a remote costs Apple $10. That's $10,000,000 saving for every million laptops it sells.
On the assumption that most users won't miss not having the remote, or won't mind paying $19 to get one, that's money well saved at little or no cost in customer satisfaction. Makes sense to me.