First, if I gave 144 people 25 bitcoins each, and they sold them, what would happen to the price of a bitcoin? According to you, the market would collapse because it cost them nothing to gain those bitcoins. Obviously, it wouldn't because there are enough free bitcoins to affect the market. You can't generate an unlimited number of bitcoins, so you can't drag the value down to the marginal cost.
Second, suppose Bitcoin was premined and 1 bitcoin was given to each of 21,000,000 people. Would the value of the bitcoins forever be 0? What if other people wanted some? What if people wanted two or more? What if one person managed to collect 10,000 and got someone to trade a pizza for them? Would the value still forever be stuck at 0? No.
Don't you see? The value of a bitcoin has nothing to do with the cost of creating it. The supply of bitcoins does not depend on their value and bitcoins are not consumed. The economics of gold, oil, and other commodities does not apply to bitcoin.
You are correct. However, there is still a psychological bias toward buying into a currency that had real work done to create vs a premine.