I'm one of those. We moved from London two years ago, bought a house with two acres of land and it has a fireplace. Our nearest neighbour is 1/2 a mile away so we can burn non-recyclable rubbish outside in a fire pit. There were a lot of old rotting wood on the property (old palettes mainly) so burning it is a good way to get rid of rubbish. You can't just burn domestic rubbish without something like wood to help it burn.

In London and other UK cities there are large areas that are smoke control zones and if you burn anything outside, it can get you into trouble. See https://www.gov.uk/smoke-control-area-rules

We have a fireplace and chimney in the main house (theres an annexe as well), and we buy the more expensive 'smokeless' coal which is better quality, burns hotter and yet lasts longer than the cheaper coal. Prices are typically £6 for 20KG of cheap coal or £8 for the same quantity of smokeless.

The chimney has to be swept once a year. That costs about £45. It prevents soot from accumulating and possibly catching fire. We also need a carbon monoxide detector because fires can give off co.

We have a lot of trees on our land and have a large stock of branches drying in an outside shed for winter but that wood is light, good for getting a fire going but doesn't give off a lot of heat. We light the inside fire typically from late October to late February. Local shops and supermarkets sell kiln dried hardwood which is the main source of warmth. Coal keeps the fire burning longer but the wood gives off far more heat.