Same reason they say to the Japanese

'You let people drink in public, but you don't let muslims pray in public, why not?'
The response was "Because it's our country."  Fine response.  Here, 

is a question considered 'improper' or 'racist' to even ask.  Even as muslims in some cities do something they never did in the places they came from, block city streets and take over squares to pray, and you're a racist and islamofauxbic* if you complain.

*Can't remember where I saw that spelling, but it fits.