According to Osho, marry the rich girl and be good to the poor. His reply is playful, pointing beyond moralistic dilemmas: choose freely, without guilt, and then live with kindness. What matters is your consciousness and compassion, not the social label of your partner. If you choose wealth, offset possessiveness with generosity; if you choose love, honor it fully—either way, be loving to the 'poor' in life.
Pick whom you wish—even the rich girl—but stay kind and loving toward those with less.