For the past 100 years or so (Diogenes of Sinope might argue the last 2,500 years or so), the rise of consumerism has made us take for granted lots of unnecessary products. Somehow the advertisers have managed to convince most of us that we need a vast array of modern conveniences to be happy and healthy. In truth, most modern conveniences are only necessary for people with particular illnesses, or occupations. I suggest you throw away you television, bed, and makeup, you'll thank me later....
Things that are a scam:
Furniture: Soft beds are necessary for burn victims and people with musculo-skeletal disease. The rest of us can quickly learn to be comfortable on the floor or a thin cushion. Similarly for chairs.
Cushioned shoes (especially insoles): The closer to barefoot you can get the better. The need for cushioned shoes for people with healthy feet is not supported by research. In fact, recent research has shown that wearing insoles may actually promote injury.
Shampoo: Do you have lice and/or some other terrible scalp pathology? If the answer is no, you can probably skip the shampoo without negative consequences. Similarly for soaping any part of the body other than your hands (or other body parts that come into contact with your mouth or someone else's mouth).
Cartridge razors: Double-edge razors have all of the convenience at a tiny fraction of the price. Straight razors with disposable blades are also nice. I'm skeptical that true straight razors (ones that need sharpening) are more efficient than disposable ones, because it takes time, effort and materials (such as strops and stones and oils and those kinds of things) to sharpen the blades. The need to shave in general may also be a scam, but I've talked about that elsewhere, so I won't repeat myself here.
Air conditioning: In some climates, like Saudi Arabia and Arizona, and for people in poor health, conditions would probably be unlivable if not for air conditioning. For those of us healthy people not living in the middle of a desert, we can learn to survive a few weeks of heat in the 90s F in our houses every year.
Makeup: Makeup is for actors and actresses. The rest of us are already beautiful.
Television: TV is the granddaddy scam of them all. TV and advertising are one of the main culprits for convincing everyone they need all of this junk that they don't actually need and won't ever make them happy.
Processed food: Stick to the produce and bulk sections, you can eat cheap and well and without much time investment.
There are lots of other scams. Let me know if you think of any good ones that I missed!