If they're married before they enlist, they're irrational if they don't examine the pay scale against their (known) living expenses and the emotional stresses service life will impose on them.
If they're thinking of getting married after the serviceman enlists, they're irrational to do so prior to examining their (known) income and their expected costs of living.
So, in either situation, if the analysis indicates a gross budget shortfall of income vs living costs, what reasons forced them to persist in their actions, and under what circumstances should the taxpayer be expected to bear the cost of their poor decision making ability?
We've got people at the airport who snoop luggage and feel people up.
Most of them are government employees, and free-lancers who get caught are punished.
What's the problem?