Some people do use heat and some don't. I don't have heat and am in Scotland, however today it is about 10c out there so they are in the house with the lamps on
With this summer(!!!) they are out and in like fiddler's elbows. If the weather was settled they would be out all day and night with no heat.
Putting in electrics outdoors can be tricky as you have to be careful about condensation etc as wet + electric = death usually