The problem with theme parks and fairgrounds
I always worry about the same thing at fairgrounds and theme parks: will my wallet/money/keys fall out of my pocket while I'm on the ride? The solution as a youngster is simple: 'dump everything with mum'. My other worry is that my glasses will fall off; if you remove them for the ride then the blurred vision makes the ride less enjoyable.
If I were a theme park boss I would manufacture cheap - flimsy even - bags that can be attached simply to a belt or belt loop. The idea is that the bag would contain all the 'pocketables'. The bag would also contain an elasticated cord that can be attached to the ends of a pair of glasses.
Of course, these problems are preventable with a little foresight, but how many realise the problem when it's too late?