It is not all about money. In fact, the amount of money top soccer players earn ruins their soul in the long term and destroys their self discipline that got them to the top in first place. As a result most of them end up as cocaine addicts or alcoholics by the time they reach their 30's: see George Best, Paul Gascoigne, Diego Maradonna, Stan Collymore, Paul Merson etc; the list is long.
I would not say that professional soccer players are not particularly fit either. Even the best of the best at teams like Real Madrid or Manchester United would all get completely and utterly destroyed by Mary Cain in an 800m or 1500m race. On top of that, they are always playing matches and pick up a huge amount of injuries due to the nature of the sport. By the time they reach middle age they are basically physically handicapped. Not a good way to be no matter how much money you have.
Finally because they are paid too much money, most professional soccer players tend not to pursue an education and many grow up to be essentially illiterate. Distance runners on the other hand tend to be university educated and are much better equipped for dealing with many of life's matters that require a bit of thought. So if this Bale or whatever his name is really had Rupp-like distance running talent then it is a shame for him that he has gone the route of football. But it his choice to make of course.