There’s a lot of weird stuff on here about smart meters. Wheniwasyourage explained about the issue with mobile signal. That makes sense.
But using the readings to know when you’re away from home? It’s more likely that the guy walking past notices the house has been empty, not that someone in the utilities agency is monitoring your individual readings to see if they can come and burgle you.
Energy firms won’t be designing a plan just to target your high usage times, they can already see when the high usage times are from the electricity that has to be generated. They’re not watching to see when you put the washing machine on to charge you, individually, more for that particular period of the day.
The second generation meters will work with any supplier, so although it used to be an issue changing suppliers, it's less so now.
And they are meters, they measure and report on what you are using. So any suggestion that users might not get the best deals or can be easily switched off is a bit far fetched. Far more likely that the people who won’t move on to the system that causes least effort for the suppliers won’t get the best deal.
But, it’s a free world. Anybody can decide for themselves how they want to do it. Just please be aware that there are some unlikely scenarios being talked about.