Residential composting services is a mostly urban, and sometimes suburban thing. Composting is harder if you live in an apartment and don't have land to put a compost bin outside, for example. Some people in that type of living situation who care about the environment and want to reduce their waste, or go zero waste, are willing to pay the premium for such a service.
Also, professional composting services may be able to handle categories of food waste that doesn't as work well in a home compost bin, such as bone/meat scraps, because the commercial processing of compost tends to allow for higher pile temperatures and more regular maintenance than a home compost pile. Plastic-free take-out containers and utensils billed as "biodegradable" are also unlikely to break down in a home compost bin.
And many composting service companies focus on commercial clients in addition to or instead of residential clients. Restaurants are an especially good match for this type of service. Many offices in my area subscribe to composting services, or at least did pre-pandemic. The company puts a compost bin in the office rec room/pantry area for employees to dump their lunch scraps into, and the composting service empties the container on a regular basis. Theaters and concert/festival venues sometimes have composting contracts to. It's definitely not just for home gardeners anymore!