NO! unless the whole house is RCD protected by 100mA. You MUST have a
trip on the appliances as these are he most likely things to develop an
earth leakage problem. Agreed this is not normally a shock problem
unless the metalwork gets de-earthed by e.g. corrsion.

"MUST" is a bit strong. There is no requirement in the regs to RCD protect
such circuits. If safety is your concern, the 40 quid additional cost of the
RCBO would be better spent elsewhere, like on additional fire extinguishers
or an escape ladder, or non-slip paint for the door step, all of which are
far more likely to save you from harm than the slight possibility of a
double fault occuring in an appliance whilst you are clamped to a good earth
in the kitchen.

It also strongly increases the risk of a nuisance trip taking out the
fridge/freezer.

Christian.