Islamic business and business as usual: a study of firms in Egypt:

Fifteen Egyptian firms producing goods and services were classified into two sets by method of finance, i.e., profit-sharing for the seven Islamic versus debt-at-interest for the eight non-Islamic firms. Interviewed in 1993 and 1994, the two groups were found to be similar in customer relations and market behaviour and in paternalism toward employees. However, the non-Islamic firms had a significantly higher average profit rate, while the Islamic firms paid a significantly higher average wage, suggesting that cultural institutions shape economic behaviour even in a well-established market economy.