"Charity begins at home" implies enabling the "soul or self" for merger with its Origin or Supreme Self. So long as the "soul" struggles in sheltered bodies of life and death, keeps on settling karmic rentals on a daily basis and creates additional karmic liabilities, how can such a distressed "being" be charitable? When the mind is polluted with the fire of five perversions, sentiments of selfless service with humility and devotion cannot emerge.
Mother Teresa, an evolved soul, practised charity of compassion. Says Jesus, "Let not thy left hand know what thy right hand doeth and thy Father which seeth in secret himself shall reward thee openly." The mystic concept of Charity is the emancipation of soul, not temporal comforts riddled with pain and pleasures.
The commercial kindness of "Rob Peter to pay Paul" carries karmic retribution. Guru Nanak's concept of service to mankind embodies three conditions: one's earnings must be honest, offered with remembrance and gratitude to the Lord, and those beneficiaries must utilise amenities for honest living. Donating indiscriminately to institutions of questionable integrity is forbidden due to Karmic reprisal to all participants in the string. Economising on the five elements of Nature — water, earth, air, fire, ether (sky), including environmental cleanliness and frugal lifestyle — is akin to Charity.
Unfortunately, the visible charity of display of wealth is prioritised over righteousness of self. That's why such services are of limited utility. How can those who are uncharitable to their own selves prove charitable to others?