Businesses obviously care about the ethics of their managers and employees. Managers who embezzle large sums of money can destroy a firm. Sexual harassment by employees may lead to multi-million dollar legal settlements. A firm may be hit by substantial fines if employees lie to customers, misrepresenting the features or risks of products. Firms may want to maximize profits but they certainly do not want employees who try to line their pockets by whatever means possible.
Firms equally care about the ethics of their customers.
Retail stores suffer huge losses each year due to shoplifters. Unscrupulous customers buy pieces of clothing, wear them and then return them, thereby depriving stores of deserved revenue. When customers are very abusive, firms may find it difficult to retain employees willing to serve the public. In more general terms, businesses must care about ethics because businesses are part of a human community. Communities are held together by virtues and sound mores.