Swiss religious accommodation issue misses the point

A story from a small town in rural Switzerland has once again brought into sharp relief the thorny issue of religious freedom and accommodation of religious views.
Two Muslim teens, aged 14 and 15, who have lived in Switzerland for many years (their father, a Syrian imam, was granted asylum there in 2001), have refused to shake hands with a female school teacher, which apparently is something that Swiss kids are routinely expected to do as a mark of respect. At first, the school granted them special dispensation not to take part in the handshake ritual, suggesting that they don't shake hands with male teachers either in order to avoid charges of gender discrimination. But local people have taken umbrage and, more recently, the family has had their Swiss naturalizations proceedings put on hold as a result of the uproar.
Now, while you could justifiably say to the Swiss authorities, "get over it already, this is not important", apparently shaking hands is a big deal in Switzerland. The two brothers' refusal is on the grounds that physical contact with women who are not family members is against their faith. To me, as a non-believer either in Allah or in any other God, this seems even more childish and unjustifiable than the Swiss authorities' stance. Even the Swiss Federation of Islamic Organisations have confirmed that there is no reference in the Koran that would justify a refusal to shake a woman teacher's hand (although the smaller Islamic Central Council of Switzerland say that a handshake between men and women is indeed prohibited by Islam).
I have no time at all for people intent on applying random medieval tribal beliefs to modern day multicultural society, and I kind of feel sorry for the Swiss administrators who are caught in the middle of such infantilism. You can almost see why so many countries are currently balking at taking in more Muslim refugees. The initial problem arises, though, from the politically-correct impulse to accommodate religious views, and to bend over backwards in trying to reconcile various disparate religions with modern secular life.
Now, I may be taking a harder line as I get older, but it seems to me that, if an immigrant's religious views are not compatible with local customs and norms, then they should probably take them elsewhere. After all, these people chose to go to live in Switzerland or wherever: the least they can do is to try to fit in. Sure, pray and fast and do whatever you feel you have to in your private life, but don't expect the host country to change itself to fit around you.
I too am an immigrant, here in Canada. It was my choice, and I am grateful to be here, so I obey the local laws and cultural norms, even if they are not those of my youth. Granted, I have not found that particularly hard, but surely the same principle applies even where an immigrant has to work harder, or make more changes, in order to fit in with the local way of life. A principle is a principle, is it not?