On a security note, do Chessington operate searches? Only ever gone in via hotel so no idea
Yes there are tables by each entrance, on the North it's by the turnstyles (iirc) and South is on the road that runs from the field car park, which of course means if you park in the MAP carpark, you can if quick bypass it before they see you.
I've never been wanded at Chessington, but I have been waved through because I didn't have a bag, or because I walk in from the MAP carpark, been shouted at, replied "haven't got a bag" and been told "ok carry on". I mean, you'd have though at least one member of the security team watched Deadpool 2 and realised just how much crap you can fit in a fannypack under your jumper lol.