The sunlight readable displays have heavy anti-glare treatments but tend to be smaller displays.
What you are asking for does not exist today. Anti-glare? Yes. Glare proof? No.
The price on the Apple was only 50 and not 100 USD last I looked. As to your second question WHY? that is something you can ask the makers.
Bob
I will soon be in the market for a laptop. While small screens are cute, they're not practical as my eyesight is not so good. I need at least a 17" display. I've gone from store to store without success because I must have a glare-proof screen. i find the glossy screens very attractive and bright but too annoying. I notice that screen filters are available that fit-over glossy screens to make the screens appear glare-proof. How effective are these or are they merely junk? How exactly do they attach over the glossy screen? Do they use adhesives which could damage the screen? There is little information about this matter anywhere. Few manufacturers produce glare-proof screens and those are usually higher-priced. Apple charges an additional $100 if the buyer wants a glare-proof screen. Why? Are these more costly to produce? Are there any good filters on the market? Do they attach to any laptop or only to certain brands? They seem reasonable (under$50).

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