I always wonder if these "well paid jobs in the city" are devoid of stress and burnout, and are bastions of morality, and exist in sufficient numbers to satisfy the default position of dissuaded, disillusioned or failed commercial pilots? Come Five o' clock on a Friday evening its Bowler and umbrella off the hat stand, hop on the commuter train home and look forward to a weekend flattening daisies in your very own light aircraft.
Flying has provided me with a very good career and there is no doubt a lot of luck was involved, but it is still a reality that there are good jobs out there. I am very lucky in that I see a stream of people entering a profession who are also getting a good start to their careers. The mechanics of entry have evolved over the last two decades as indeed the industry itself has evolved.
For those that really want a career as a professional pilot in 2014, I doubt that telling them why they can't, won't, shouldn't, or mustn't, is going to make very much difference. You can spell out the realities, you can recount tales of horror, you can highlight each and every pitfall. Some will heed the advice and use it as a part of their journey, others will simply believe whatever they choose or simply have to believe in order to justify a limited range of options. You pay your money and you take your choice!
As posters above have said, it is a job and once the illusion of glamour has started to tarnish it is still a job. It is what pays the mortgage/rent and pays the car bills and the food, loans, credit cards, clothing, heat, light and entertainment. Monthly bills get very mundane, and remuneration is what (if you are lucky) keeps them mundane rather than a personal crisis.
The roads into the better remunerated jobs are either very expensive or very long. Often they can be very expensive and very long. There are no guarantees. The risks are enormous. Crossing the raging torrent to these better remunerated jobs is fraught with difficulty. There are plenty of "I have no agenda" folks, clinging on to these slippery rocks telling others not to pay the toll to cross the bridge.
Would I promote a career in commercial aviation to my own children? No, not beyond many other choices that may be available to them. However if they were determined to take this route, then I would provide a very detailed and specific roadmap to help them achieve their goal. That roadmap would be full of many of the same warnings that are highlighted in this and many other threads.