In my opinion and also in yours, when we give something for charity to any needy person it is not any obligation or favor to him, but is merely the payment of royalty on behalf of God for what we use as the raw material of what we produce and earn if we are a manufacturer. If we are a businessman or professional, we pay the levy of our intellectual property borrowed from Him. If we are a farmer, we use land, water, seeds etc. provided by Him. If we are a laborer, we pay Him for the physical strength He favored us. Nothing is ours, everything is His. Even we-ourselves are in existence at His will and our every breathe is dependent of Him.