I guess for the economy to tick over we all need to be purchasing something.I agree there often isn't any point replacing working old for new to simply save money.
Running cost isn't the only reason people replace appliances. Some times people do just want to spoil them self and replace the old 20yo tv to take advantage of bigger screen size, better picture, esthetics.I like my mod cons and new tec but I try and buy quality and get some life out my appliances.
We replaced Our first refrigerator (small) for a larger one once we had a family and simply because we needed more room. Although we purchased a like new fridge from a friend who was moving overseas. New people are always entering the market some purchasing there first tv,refrigerator ect.
The cost of the more efficient appliance isn't always more. We purchased a 100cm Samsung LED tv I think its consumption was around 173kwh PA (that was based on a lot of viewing hrs per day) and uses 30 - 45w . It cost around $500 (after a lot of haggling)
When i was looking There was plenty of other tv's same technology (led) and screen size (100cm)that consumed a lot more KWh PA and were more expensive. For example there was one Loewe tv (led) 101cm that consumed 640kwh!!! PA(buggered if I know how they manage that from a LED tv. Unless it has a built in air conditioner unit

. That's 3.5 times more energy than the Samsung , There was a CHANGHONG (sounds like a cheep china home brand import) that used around 400kwh same size and LED. Unless there's about 100 misprints in the gov energy rating webpage there are some chocking consumers out there. Jump on there and do some searching.
For people off the grid keeping the consumption of appliances that spend a lot of time on each day to a minimum can make a big difference to the size battery, inverter, PV's you need to invest in.
Some one with a good size plasma, big double door refrigerator with ice maker and a few power hungry desktop pcs running all the time might need a system that costs double what some one with energy efficient appliances dose. The saving in not having to Double the size of a off grid system would more than cover the cost of new appliances.
As for the OP. I think your concern is to save money. Its a hard one as anything you invest in to save you on consumption is going to have a very long pay back period.Or any thing free or cheep could potentially look like a ugly experiment.
Kurt