There is a verse on this subject. If a guest goes away from a house with expectations not fulfilled, he is supposed to take away the merits of the householder and transfer to the latter all his sins.
भवन्ति चात्र श्लोकाः-अतिथिर्यस्य भग्नाशो गृहात् प्रतिनिवर्तते। स दत्त्वा दुष्कृतं तस्मै पुण्यमादाय गच्छति॥