Have you been to Egypt? Senegal? Iraq? Morocco? My experience is different than yours, apparently. I go to Egypt a lot, and the demand for bribes has been overt and continuous. I don’t see it as something that is any more or less likely in an Islamic country than in a non Islamic one with a similar economy.
“Baksheesh,” the smiling guard supervising the line will say to you, as he holds out his hand in a welcoming gesture. If you are moved to give him $10, he will be moved to let you into the line.
“Baksheesh,” the smiling customs inspector will say, as he commands you to open your luggage. There is a $10 fee for the inspection."