Well, the amount invested is not really a concern when provided the return on investment is still higher; and if billions can be invested on movies like Matrix, Titanic and others and why not for spiritual purpose.
And concerning clean water, proper nutrition etc.., that is an issue for food for the body and not food for the soul. And if you wanted to outline about the opportunity cost of spiritual investment then also you need not worry because proper utilization of resources (with respect to basic human necessities ) can only happen when the term Svadharma becomes clear to the individual.
And also humility and simplicity are the by-products of spirituality and if there is no initiated investment, we cannot even think about them.
Last but not the least, any judgement is done by considering the 3 factors, the object itself, time and circumstance. We need technology to infuse spiritual culture to the upcoming generations.