This is definitely going to be a personal preference, I'd think. If somebody who is 'old enough to know better' wants to carry a silly youthful bag, more power to her.
I personally carry what I like, regardless of who the bag is intended for (read: target audence).
Side note: I saw a woman yesterday who
had to be in her seventies, and her hair was black as the ace of spades. From the back, OK. From the front - it's like, lady, grow UP already and get over it. I didn't notice her bag, she was too busy trying to get her groceries carried out for her. Attidude with an A. Come to think of it, who would dare tell her that dying her hair at her age is silly ... Well, I would.