In the motorway service station industry, the word operator is used to refer to a single company/brand name who (as far as the public know) are responsible for providing the facilities at a service station.
The operator's name will usually be advertised on the motorway signs and around the building, and they will be the first point-of-call for customer enquiries. A list of operators can be found on this website.
The term 'operator' is deliberately used to offer customers a simple and recognisable point-of-reference. The reality is often a little more complicated.
Increasingly, parts of a service station may be leased out to another company. This means there is not actually one company operating the whole site, but two or more. Only the main landowner will usually regarded as the "operator", and they will pass on any enquiries.
Many A-road services have been built by a land management company, who then sell different parts of the land to different companies, meaning there is no operator by our definition. It is clearer to refer to each of the facility providers as "owners", but sometimes 'operator' will be used to describe the owner of the main restaurant, if there is one.
Margram is an example of a company who engaged in a similar strategy, but as they owned motorway services, they had to give a brand name to use on the motorway signs. They gave the name of their main facility, McDonald's. This means McDonald's is the operator and Margram was merely the company who owned the land. However, this could cause confusion with McDonald's' wider business strategy, so in this case a clarification is normally required.
A number of petrol companies have bid to run motorway services. Normally they will lease some or all of the facilities to a catering company: for example BP won the contract for Killington Lake but leased the facilities to Roadchef. Often, that catering company will then be treated as the operator, and have their name displayed on the signs, even though they don't own the main lease.
Although companies no longer have to bid to run motorway services, the same process has happened with petrol companies buying land and leasing parts of it out.
The term 'operator' dates back to the earliest service stations, where companies were invited to submit their plans for whole service station developments. If they won the contract, they would have to inform the Ministry of the brand name their company would be using in public.
The regulations allowed only that brand name to be advertised, and they came to be known as "the operator of the facilities".