From my (limited) understanding, Islam demands that women dress modestly but there is no mandate on what women should wear; and this is completely reasonable being that it allows women the freedom to choose what is appropriate to wear in different contexts. In other words, being against the burqa can not really be seen as religious intolerance being that it has nothing to do with the religion.
With that said, I think it is entirely reasonable to create a legal framework to ensure that people have the right to refuse services to an individual if the way that they’re dressed causes significant problems. The most current example from Canada is that a woman refused to remove her hijab (face veil) while she was being taught to speak french; as you can probably imagine, it is virtually impossible to correct a person’s pronunciation without being able to see their mouth.
