In article , Chris French and Helen
Johnson writes
In message , Kay
writes

The noise of smashing glass might attract attention. Having to smash
glass rather than just walk in may well be enough to deter the casual
thief.

After all, if you follow that argument, why bother with window locks?
;-)

Because house are worth getting into, most greenhouses aren't.

That's actually supporting my argument! ;-)
We bother with window locks even though 'all a thief has to do is smash
a pane of glass' - in other words, we consider having to smash glass a
deterrent in a situation where there's something worth stealing the
other side, so there's no reason to feel it wouldn't be a deterrent in
the greenhouse situation (except, as you've pointed out, the more
careful thief can remove a few clips)

--
Kay
"Do not insult the crocodile until you have crossed the river"