Girls and boys can be just friends. Well, I agree with that. However, I have two issues with the way those two movies portray this "close male friend."
First, why do these Cinderellas have no close female friends? Sure, they're oppressed by women (a stepmother, stepsisters), but that still wouldn't keep them from having female friends. Or perhaps they just get along better with guys, well, that's okay, but just ONE guy? Who you tell EVERYTHING too? Seriously? Surely at least once the guy thinks "Wow, I want to kiss Cinderella!" But no, Cinderella was over him last month. This month is "Prince Charming" and how he "might" notice me!
That brings me to my second point. Why doesn't Cinderella marry her best guy friend? What that best guy friend knows about her is more than the Prince might ever know (especially since there are things you know from growing up with someone that are hidden from people when you're older). Especially since the princes are so shallow. They're disappointed when they discover who their "princess" really is. Seriously, that boy who has known you your whole life is not disappointed when you are yourself. And I just have to feel a bit of a pang for them. Cinderella was too good for him.