I’ve had this same discussion with a few people who prefer reading on tablets. My experience is that they simply refuse to acknowledge that glare is an issue. “Why the hell would I be reading in direct sunlight? I’d just go find a shady spot,” is the typical response.
I have a Kindle Voyager (the brand spanking new one with an even higher resolution than the Paperwhite and with buttons-ish!!). It’s far better than reading on any tablet screen I’ve ever witnessed. I think it really does have something to do with the front-lit vs. back-lit - especially if you are reading before bed and all other lights in your bedroom are off (I find phone or tablet screens in the midst of that darkness to be too harsh).
And yes, there definitely is the outside reading thing.
As someone who has settled with a tablet and iPhone for reading (because I also want to watch movies and browse the web), I can tell you that it’s not really such a big deal to go find some shade. I certainly acknowledge the glare issue, but it’s never been a problem that prevented me from reading when I wanted to. Even if my only option is to shade the screen with my hand, the reading goes on.
A book-only device like the Kindle is simply not a good option for me. Maybe someday when I’m Mr. Moneybags and my butler can carry around a suitcase full of my single-purpose devices for me. 
If Anaamika ever got her wish (a device with both LCD and paperwhite display modes) then I’ve be right behind her in line to get one.