grammaticality - Is vs Are; why do they use the Are instead of the Is?

A company such as Vodafone can be considered to be a large group of people, therefore plural, or a single organisation, therefore singular. So you can use either:

"Vodafone are providing a useless service" is equivalent to "The employees of Vodafone are providing a useless service".

"Vodafone is providing a useless service" is equivalent to "The Vodafone company is providing a useless service".