Putting the compresors outside would definitely be more efficient. Quite a good idea, actually, if they can be well sheltered form the elements (except the cold, of course)
We'd really struggle to get by without the walk-in fridge at the moment, though it is possible we could get rid of it eventually with a bit of careful organisation.
As for the walk-in freezer, I believe we can de-activate it soon if the kitchen people manage to reduce the amount of bread and burgers we are having to store. I believe they are discussing it.
Is it possible to switch off the freezer and leave the fridge running?