I think the ban is only public schools and sometimes governmental buildings. This is different then the religious mandates which are restrictive to all non-private space.
In France the law is actually all displays of religious affiliation within government run schools. This is more akin to the banning of gang signs and colors in various schools in America.
To compare these bans to sharia is ridiculous. Sharia laws typically enforce mandatory burqa and other attire for women in
all public places. Also, there is a good amount of sectarian violence in Islam where certain articles of attire are viewed as important by one sect and not so by another. Often a tolerant nation will ban sectarian dress in order to prevent violence in the streets.
Anyways Islamic and all religious practices have no place in a secular government, and exclusion of religious practices and overt religious expression within governmental spaces is constitutionally legal. The basis of secular society is the non-interference of any religious majority within the government. It is not a podium for religious expression, and this is why religious attire is banned.
As a whole in the history of man, religious groups have always been in opposition with other religious groups and non-religious group, to the point of genocide, enslavement and gross exploitation.
What's the punishment for apostasy again?
YouTube - Richard Dawkins - Apostasy In Islam Carries The Death Penalty
That's right... death. Here's to keeping religion out of government.