This is not the case.  Like everything else with religionists who rely on a book for their laws it is open to interpretation, which in itself is a basic flaw but allows control over the populace by the Imams.  So you get nutters in all religions.  Unfortunately a lot of nutters in Islamic countries are in power and therefore Sharia Law is enforced.

I like to tell the tale of when i was in Sumatra, Indonesia - most populous muslim country.

 A friend and I got on a bus.  There were two seats free. One next to a married elderly woman and one next to a 30 something married man.  We didn't sit down we just stood.  20 secs later the 30 ish man got up and sat next to the woman so we could sit down.  We appreciated that and thanked him and the rest of the bus nodded in approval that we had respected their customs.

2 days later I was enjoying a coke in a cafe with two Indonesian school girls aged 14 and 17 (dressed in red dresses, white shirts and white socks, no head covering at all) finding out what the Indonesian word for belly button was! 

We all learnt a great deal about one another.