As In Catch 22 or The Chicken & The Egg
The flawed assumption on your part is the need to move large numbers of people and supplies to Mars. The reason Mars is the best target for colonization is that it has the resources to grow a colony. Many have pointed out that Mars oneway is even cheaper than Mars Direct. Of course I happen to think that's a bad first trip plan, but is entirely reasonable when colonization is the goal. Of course a thriving space industry would also be a way out of the paradox.
Regards,
Mark