Casual use on the couch, in bed before going to sleep, something for guests to use when they come over.
For these types of use-cases, a one-piece tablet easily beats a clamshell/laptop configuration, hands down. With an iPad you don't have to fight with balancing the device on a flat surface, and you can use it in any orientation, even lying on your back. And if you really feel the itch to type on a physical keyboard, pretty much any bluetooth keyboard will work fine with the iPad.
Considering you're also already in the apple ecosystem, the iPad clearly has the advantage. Sure, you'll be saving a little cash with the Chromebook, but then you'll be jumping through all kinds of hoops to integrate the Chromebook with the rest of your devices.
Don't get me wrong, Chromebooks are great, and I'd happily use one if I were all tied up in Google's Cloud, and trusted all my stuff there. But, I don't.
I like local storage, and I like having direct control over what goes in the cloud and what doesn't.