You have to hold the investment for at least a year to get the reduced Capital gains rate. Short term gains are taxed at regular income tax rates. I wouldn't consider someone that holds an investment for a year or longer to be gambling. They are investing but the question becomes why should people that earn money one way be treated differently than those that work for a living?
Good point. They aren't adding any value to the economy, but they aren't gambling like a day trader. I've always been a buy and hold guy unless there is some compelling reason to trade or the stock is called. That's why almost all my income is taxed at the 20%.