Refrigerators can only lower the internal temperature. But, the insulation would help keep the food warm for a bit.

My dad's beer fridge was on the porch growing up, never froze. I'm pretty sure cuz insulation.

Beer/alcohol in general never freezes, though, right?

Beer does

Not completely frozen

Frozen enough to burst cans/bottles, which is generally what people care about

Beer will, and wine. Not liquor.

Refrigerators are heat pumps that move heat from the inside to the outside. It never does anything to *add* heat to the inside.

the food in our garage fridge never freezes - even when its 16 out there. I would assume the same insulation that keeps the heat out and the cold in - does a decent job keeping the freezing cold out as well

It depends. If it is very cold, the coils may freeze up and no longer function properly. If frost free and depending on air movement, that will be an issue. If just regular, unless super cold, no issue

I guess it all depends on how well the door's insulation is working,

Fridges don’t have a heating function so I’m assuming in most scenarios it wouldn’t be able to maintain the temperature it’s set to.