Not always blistering heat. During our summer (their winter) temperatures are quite moderate in southern Africa not unlike summer weather here except much drier. Usually the hunters are taken out in a bakkie (4-wheeler) and driven around. Giraffes aren't hard to see and not particularly wary. The goof who thinks he's a Mighty White Hunter shoots from a couple of hundred yards at most and then is hauled back to the lodge for cocktails.
https://i.imgur.com/NiBflSBl.jpg
It's a business just like the spring bear hunt is here. The animals aren't game but a commodity to improve the local economy and it's easy money. If you want to make a PH earn his keep hunt kudu, buffalo, oryx, eland or some other animal that requires a little effort.