You do know that snakes readily take frozen thawed food? Even in the wild if a snake comes across carrion they will eat it.
Eh, I had a quick check to get some facts before I just tried to blurt out something completely baseless like saying they're scavengers. Ireland having no snakes and Britain having "slow-worms" isn't much info to go on, y'know?
Britain has snakes too, like grass snakes and adders. Irelands kinda boring when it comes to reptiles.