I still have The Readers' Digest Complete Book of Fairy Tales (volumes 1 and 2) which my parents bought for me decades ago. The books' spines have been bound up with tape and I couldn't tell you how often I'd read these books. The stories are the original versions of the classic fairytales and the pictures are wonderful. It was the pictures that drew me into the books before the text worked its magic on me and I became glued to the stories themselves.
The stories have a strong moral tone (kids are often more passionate about justice and fairness than many adults are), have clear good guys and villains (which I remember loving as a kid. It's nice to know who to cheer for and who to boo!). Some of the stories are warnings against greed (Roald Dahl was brilliant at this too). Others are warnings against dangers (for example, Little Red Riding Hood is a good warning not to be taken in by appearances).
Some stories don't have the classic fairytale ending (The Little Mermaid and The Little Match Girl both end sadly) yet there are still plenty of happy ever afters too. So what is there not to like about fairytales? Nothing!