We stayed at the Bonjour, in an apartment with a fridge.
We ate out all week so did not use it to keep food in, but we did use the freezer compartment for iced water and the fridge for cold milk.
I think the maids try to save electricity, maybe?....but the fridge worked separately from the air conditioning and the lights, so stayed on all day, even without the key in the slot.
The
hotel section may be different, as I imagine they would not want you to use a mini bar for your own stuff.
Self-catering apartments, however are self-explanatory and you should be able to keep food and drink in the fridge if you want to...not everyone can afford to eat out every day and night.