> It's sorta up for debate.It's also a very broad question, kind of like asking "Is science good?". On the one hand, science has brought us all sorts of good things but it's also yielded weapons of mass destruction. (Ironically, Warren Buffet once famously - and presciently - described derivatives as "financial weapons of mass destruction"[1].)
> So, you enter a contract to sell your crop at a fixed rate long before harvest comes along. That's a future contract...
Technically (and pedantically), that's actually a forward contract, which is, admittedly, very similar in nature to a futures contract[2] (and, typically, a forward contract will often underpin a futures contract) and a perfectly excusable error to make. The reason I point it out is not to score a point but to highlight the distinction in order to illustrate how esoteric the financial markets can be.
Their esotericness/esotericity (clearly not real words but I think you get my point) means that the specialised knowledge and skills are highly valued. We generally accept that a ninja/rockstar engineers can be 10x as productive as an average engineer. The distinction is even more marked in finance - not only can a more knowledgable, better-skilled, more talented person make more money than someone who isn't as good, but the latter can end up actually losing large amounts of money (e.g. JP Morgan's London whale[3]). I learnt this the hard way just a few weeks into my (short) career as a trader when I made a very simple mistake and lost $16,000. Do that once or twice a week, and you'll easily end up down over a million dollars over the course of a year. To avoid "fat finger" errors, you need to be capable of being very focused for (in my case) up to 12 hours a day (or, at least, being able to switch from "relaxed, joking with your work colleagues" mode to "laser-focus" mode in a split second). Not everyone is capable of doing that. Some people can't handle the pressure. Others simply lack the brain configuration required to do it - they may well be smart, intelligent people - it's just that it's a very specialised job and some people's brains are going to instinctively better at it than others.
Add to that the fact that the financial markets are, by and large, a zero-sum game (which means that the best guys can actually take money off the not-so-good guys) and you have a situation where the top talent are able to demand (and end up feeling entitled to) the sort of pay packets mentioned in the original article.
It's a bit like Mayer hiring De Castro at Yahoo![4] - if he'd turned Yahoo!'s advertising business around, the company would have earned $600m more revenue over the past year, and a $60m pay package wouldn't have looked so crazy. If a bank hires a rockstar trader away from their competitor by offering a salary of $3m and he makes a $300m trading profit over the course of the year, it's a pretty good deal. On the other hand, of course, they could lose $300m and this was traditionally an asymmetric, one-way bet (i.e. if the trader made profit, he got a bonus but if he lost money, he didn't suffer any downside, which meant that he was implicitly incentivised to make big, dangerous bets) until new rules came in around claw-back provisions (so previous year's bonuses could be reclaimed if it turns out they were based on phantom profits) and paying bonuses partly in shares (thereby linking traders' fortunes more closely to their employers').
I still work in finance but back on the technology side of the fence (I'm basically a freelance product manager for an in-house piece of software that's used by a couple hundred people globally). I spend 25% less time at work than I did as a trader (i.e. 9 hours maximum instead of 12), the work's a lot less stressful and I find it interesting/challenging/fun. Whether I'm still doing it in six months time (as opposed to, say, working for a startup) is anyone's guess but the perceived social worth (or, more accurately, the lack thereof) of finance in general wouldn't be a factor in that decision.
[1]: http://www.berkshirehathaway.com/letters/2002pdf.pdf
[2]: http://www.investopedia.com/exam-guide/cfa-level-1/derivativ...
[3]: http://en.wikipedia.org/wiki/2012_JPMorgan_Chase_trading_los...
[4]: https://news.ycombinator.com/item?id=7068455