Hetherington responded to a report by sports finance specialist Rob Wilson, from Sheffield Hallam University, for the BBC Inside Out programme which claims Super League clubs are on the edge of "a financial abyss" with combined debts of more than £60million.
Hetherington, who founded Sheffield Eagles in the 1980s and was a leading force in the switch to summer rugby, says the Rhinos have made a profit in each of the last nine years but concedes that mismanagement has caused problems at other clubs.
"We're becoming heavily dependent on television revenue and also historically on benevolence," Hetherington told BBC Radio 5 Live. "Where you find a problem, it's generally down to poor management from the top and often the withdrawal of a benefactor. The more underlying issue is the management of professional sport.
"I think there is a tendency in all our sports where the management tend to focus on things like buying new players, changing the manager, appeasing the fans and reacting to pressure from the media rather than having a clear focus on growth and creating a surplus which can then be re-invested into the business.
"We have a salary cap which should enable clubs to be profitable or at least break even. Given that there is more money coming into the sport than at any other time, it ought to make us very sustainable.
"I think in most cases now, clubs will be looking towards being sustainable. There have been some casualties in recent years but I think the sport will certainly have learnt some lessons from those and it's in a much stronger position now to go forward."
Hetherington, who is also chief executive of rugby union championship club Leeds Carnegie, believes rugby league compares favourably with other professional sports.
"I don't know why the focus is just on rugby league," he added. "The more interesting debate would be to look at all professional sports in England.
"If you look at the 92 football clubs, the 30-odd rugby union clubs and even county cricket, almost all of them lose money and are very dependent on both benevolence and banks. So I think it is a real concern generally. How sustainable is it?"