Well this a rather disingenuous post.
The suggestion to replace kettle with a one cup was mine.
The post said that when our kettle gave up the ghost we replaced it with a one cup simply because DH is the only one who used the kettle, so it was cheaper for our lifestyle to replace it with a more suitable device. But the post clearly stated that the old kettle was defunct.
Heating a whole kettle for one cup of tea makes no sense. Yes if you are brewing up for several people at the same time, but not for one person. One works better for one household but not another. And the key isn't to replace before the end of the life of the product unless it's so inefficient that it no longer is worth continuing to use the product (this is rare)
For me, the key is to think about your lifestyle and only replace things if you need them by thinking about not only the purchase price but also the price of running the equipment.
Usually though the problem tends to be that the more efficient equipment tends to be the most expensive to buy, but over the lifetime of the product will cost someone less. This automatically means that richer people have an advantage.
That Does Not mean people shouldn't buy those things, regardless of whether they are rich or poor. But they should be trying to make smarter purchases where they can. The best examples of this are washing machines and fridges/freezers.
In terms of buying an electric heater, I just don't get the logic at all tbh. Just buy a none electric blanket or two. In terms of efficiency and effectiveness, for most people there is simply no need for one. The only people it might be worthwhile for are elderly who have mobility problems which means they have more problems with retaining their heat. For children and younger and middle aged ages they simply don't need one.
One of the key things here, is that people who shop more savvy and more long term and consider the cost of something over their lifetime are generally better off, precisely because they take the time and effort and dont get suck in by yellow stickers and signs saying sale - they don't respond to the marketing they look at the quality of the product and whether it best do what they want and they don't buy things they don't need.
There is someone I know who is obsessed with 'getting a bargin' and does all the money saving stuff and has all the coupons etc. Except the problem is the deal is the most important thing. She doesn't look around for the same product elsewhere, she doesn't stop to consider whether she needs the item. She has a massive shopping problem and a houseful of crap which she ends up either binning or giving away.
Advertisers use often techniques to effectively mislead or misdirect someone to a product which might not be the best, because it works.
People need to get wise to this and to really think about what they do and how they do it.
One of the things people are considering resorting to is to switch all appliances off overnight. Including the fridge. Councils are making a point of stressing not to do this because it could be a health hazard and because it costs more for a fridge to get back to optimum temperature and its bad for the life of the fridge because they are designed to work constantly not be switched on and off.
Even the way you purchase disadvantages people who are harder up too though. I can stick a large purchase on a credit card and not have to pay it for 60 days and then pay it off immediately. So I have 60 days to save up if I don't have the money immediately which is interest free. But if I'm poor and have a poor credit rating, I won't have a credit card and if I need a large purchase in an emergency I might have to buy on finance on or a payment plan which is more expensive. Where this is really dumb is if its a non urgent purchase. And we are seeing people buying clothes more and more on debit which isnt controlled or monitored which is a recipe for disaster.
Everything lends itself to be be easier if you are richer to begin with.
If people start to think more about efficiency and effectiveness regardless of income its a good thing over all and a trend we should all be encouraging. That includes reducing waste and not dumping stuff which is perfectly usable though...