I would think that the one advantage of being queen is that you have staff to carry things about, or could get your clothes made with pockets so no need to have an annoying handbag!
as probably mentioned, theory is that the kids are dressed like it is the 1950s for photos, and normally the rest of the time to give them some chance of blending in. I doubt they actually go out like that.
poor example but that's why Michael Jackson had his kids masked when they were with him, so no-one knew what they looked like when they weren't with him.