The reasons for war go far beyond profits.
In this case, the incentives are many:
- Intense religious belief (in this case, Iran's desire (Ahmadinejad's desire) to usher in the Hidden Imam).
- Propaganda (gets support from the people)
- Dogmatism (support from people)
- Struggle for resources (oil, water, arable land)
- Power (either the desire for power or the desire to overturn power)
- Hatred (justified and unjustified)
- Human rights violations (and thus strong offense)
- Mis-percieved rights violations (and thus strong offense)
- Old familial, tribal, racial, and personal unresolved conflict.
And remember, many people aren't thinking clearly when they go to war. The size of the war doesn't matter - people don't plan World Wars, they plan wars that escalate beyond control, and the realization of the consequences only occurs after.