Aside from the fact that Apple DOES do advertising, you have to understand that even outside this - your data is valuable to apple and they take steps to keep it turned on. In some cases they are contractually obligated to collect the data.
Here's the thing -- by circumstance they are like arms dealers stuck selling arms to both sides. They must entice app developers to develop for their platform, and they must also entice consumers to buy their products.
Personally I think if apple was concerned about privacy, they would let you see what your phone is doing, and let you firewall your phone (one that could block apple traffic).