It is the government that is insisting on it, bookbinder, and the energy companies have no choice but to promote them.
"The government requires energy companies to install smart meters for their customers, and has set out rules to ensure that they do this in a way that is in the interests of consumers, including rules around:
data access and privacy
security
technical standards for the smart metering equipment
meeting the needs of vulnerable consumers
Smart meters will be rolled out as standard across the country by the end of 2020. But there is no legal obligation on you to have one."
https://www.gov.uk/guidance/smart-meters-how-they-work