I agree it's small fry, and evidently so do they, because hardly anyone ever leaves, despite the moaning and groaning. Only Harry has left voluntarily and look how that turned out! They are the ones who decided to add the frankly bizarre 'standing outside the hospital with a newborn baby being gawped at by strangers" element, when they could easily have said 'sorry, I'd like a bit of privacy after giving birth and the crowds of weirdos are causing issues for ambulances'. It's not traditional, and only happened for the last 2 generations. They do these things because no matter the downsides, they are desperate to cling on to the Monarchy and the lifestyle it affords them for as long as possible.