An apple bred to stay crisp for a long time on the shelf and give a nice crunch when you eat it might not make the best applesauce.
Oh. I'm surprised that the difference is considered to be that great.
In the case of apples it isn't (yet?) since there's plenty of good-tasting ones that are pretty durable to begin with, but for something like tomatoes I'd be disappointed if my canned tomatoes were the ones optimized for display rather than taste.
Growing up in the South it's fairly common to see that many people think that the fruit you won't eat from the hand, for whatever reason, are often better for certain recipes of desserts and preserves.
That's because it is. Different acid concentrations, cell walls strengths, etc lead to some apples being better suited for some things than others. Kind of like fillet vs strip, it's all the same meat, but very different, and cooks differently too.
Soft, sweet apples are better for pies. Maybe throw in a couple of crisp, tart ones for texture and flavor, but you probably wouldn't want to eat a pie with nothing but Granny Smiths.
That's curious. I specifically choose Granny Smith when making apple crumble! They are hard and almost sour when fresh, but are broken and humbled by the heat.
Most pie recipes I've seen call for multiple varieties, especially from different categories http://frugalliving.about.com/od/foodsavings/qt/Best-Apples-... My grandmother used mostly Braeburn and Northern Spies, my mother uses Crispin and Granny Smith. I think a crumble might break down the apples more than a pie with its protective crust, so harder varieties might work better there.