Well, disputing about profits and even colonization of Mars, there is two more possibilities.
1. Like Australia, Mars will be a penal colony, but some day their children will be just free Martians, like Australians today.
2. Peoples, enticed by vision of wealth, will start buying one way tickets to Mars. And some day, when science will develop new, fast and low-cost drive, peoples will start to flying to Mars and back, like today we are flying from Kraków to NY by cheap airlines.