By buying bitcoin all you do is give a financial reward to those who have bought bitcoin before you. Do you want to reward these people? If you don't, don't buy bitcoin.
This is a vastly simple way to look at it. You need to buy a thing from someone who has some? Yes checks out, object must already exist before it can be sold to someone else. Goes for houses, booze or racehorses too. Yes, in fact every thing ever sold ever is simply enriching the person that is selling it to you. And we can’t have that can we?
I’d also add that I do not regret it. I’m sure the person that sold me my coin does regret it ;-)
You're missing the point completely. A product needs to be produced. When somebody buys a product, the money pays for the production costs, so the producer is compensated for the expenses as well as the invested capital, so that they can continue to produce more products. This incentivises the production of goods that the public wants. That's distinctively different from what happens when somebody buys a bitcoin. The supply of bitcoins is fixed which means buying a bitcoin can't possibly incentivise the production of more bitcoins. The money doesn't pay for production costs, it doesn't pay for taking the risk to produce something, or for having contributed anything to society. It's purely and simply giving money to somebody for having bought bitcoin earlier than you. If you're fine with that, sure, buy bitcoin. If you don't, or if you want to penalise people who own bitcoins, steer clear of it (this is what I recommend).
I think you might not quite understand how this works. 21 million bitcoin are slowly released until the year 2140. They are released more slowly every 4 years as the reward per block halves. The bitcoin is produced, mined, sold, paying for its creation. As more people want it (demand), and thus more people want to make it (supply) the network adjusts so they cost more energy to produce, ensuring they keep mining until 2140. There is indeed an incentive model at work here. It appears to work very well (on a scale of 10years out of 130+).
What you might be thinking of is stuff that was invented out of thin air, “instamined” like a ethereum, ripple, or other Proof of Stake coins (bad, for some of the reasons you have outlined). Fair launch, no premine Proof of work coins are as close as you can get to a digital commodity.
No, I do understand how bitcoin "mining" works. The supply of bitcoin is technically not fixed (although it will be in the future), but inelastic, which, for the purposes of the argument I was making, is the same thing. The fact that it's an environmental disaster is another reason not to buy IMO.
Bitcoins are pure speculation. (So I guess if by horses you meant gambling on them, then sure, horses are too pure speculation. But nobody suggests using horse bets as a store of value, while people seriously is suggesting that about bitcoins.)
