Quote from xje:
I think it's because trading doesn't actually provide any goods or service.
Let's see, here are a few other "professions" that don't provide any goods or services:
Anyone who does "preventive maintenance". For example, I buy a used car for $5k and drive it for a couple of years until it breaks down, then I buy a new one. Total cost $2,500 per year.
My friend buys a brand new car for $20k and pays an idiot and/or crook a few of hundred dollars every few months for timing belt changes, tune-ups, brake system inspections, etc. And every few weeks some little part breaks down and costs $1500 to fix. And strangely enough, it's always something that is not critical to basic transportation, but makes a lot of noise. After about 3 to five years, he needs a new car. His total cost: probably $7,000 per year, plus he loses countless hours getting the car fixed, inspected, and sabotaged.
Or an even better example: Air conditioners. You can either buy a $2000 A/C for your home, never have it serviced or inspected, and buy a new one after 3 or 4 years, or you can pay $200 every couple of months for preventative maintenance and hope that the unit lasts you 5 to 10 years. You do the math.
Next useless "profession": Dentistry. You can either brush your teeth at least once per day and expose them to a little bit of 3%H2O2, which you can buy for $0.33 per quart at WMT or thelike; Or you can refrain from eating anything that contains processed sugar. In either case you will not have a single cavity, periodontic disease etc. etc. And you will even have sparkling white teeth. If you don't believe me, look at the teeth of 30 year old humans who died a few thousand years ago. They didn't have toothbrushes or -pastes or mouthwash, but they also didn't have any dental problems. They usually still have all their teeth, and they are in very good shape, just a little more worn than ours.
What about actors, entertainers, musicians? They don't provide any goods or services.
Or has a politician ever provided goods or services?
If you are going to argue that the aforementioned professions DO in fact provide services, I will not try to argue with that. But you should also be aware of the fact that traders provide services to the public as well which gamblers in the casino don't.
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Edit: I just saw that PuffyGums summed it up more efficiently in the post above mine. You may therefore disregard this post.