I don't think anyone gets married intending to have any of the myriad of things that frequently happen in a relationship to happen.

No one gets married to be a widow, a divorcee, a trophy wife, a domestic violence victim, a caretaker to a prematurely-disabled spouse... no one expects to suffer bankruptcy, loss of a child, loss of parents....

Marrying a backpacker at least gives you a lot of forewarning as to the potential outcomes and the ability to prepare yourself for the potentially relationship-killing strain.