Sundancefisher - residential fridges and freezers are designed to operate with an ambient temperature of around 10-30 degrees celcius. When put outside in the winter the oil in the compressor will thicken so when the compressor goes to start it may take out the compressor. If it is operating when the ambient temperature is low, the refrigerant cycle will also be operating at pressures it is not intended to be at thus causing it to operate out its normal cycle.
That being said, I have done the same thing and never had a problem. If the outside temperature is lower than the set point of the freezer then the freezer will not try to kick on anyways. If they have defrost cycles though don't count on having an ice free freezer.