That would be the first thing they'd steal. Ripping out whatever it's attached to as well.
There are so many hiding places on a sailboat, some that are so good you yourself don't even know they're there yet.
I've had my current boat 6 years. Been on it every weekend pretty much, plus cruising. Including cleaning, repairs, upgrades, maint, stowing gear, etc., and I've even taken the time more than once to think about where I might hide certain things. And I just recently discovered 2 spots I'd never realized before.
They are on either end of the port settee. The cabinets on the bottom are drawers, not cabinets like on the stbd side. Pull out the drawer on either end, and there's big space behind it. Knew that, but what only recently realized is that the spaces to the left of the left (aft) drawer, and right of the right (forward) drawer, are sealed with cabinet wood. I could build trap doors in there that even if you were looking wouldn't know they were doors, and accessible only if you pull the drawers out. And nobody would ever know.
I'll post pictures in a bit just for fun, as I know your boat is different, but maybe it will help analyze where on your boat you might have or be able to create a hiding place.
Edit: pics - the space between my foot and the drawer cavity. My foot is against the board that is the back of the chart table, which also encloses the aft of the hidden space below. There is a sealed board inside the drawer cavity that can be seen. I can convert it to a door with hidden hardware, allowing access to the space.
I'm sure there's a space somewhere on your boat that nobody would ever look at.