Some women wear it because they choose to. Some wear it because they are forced to. And some wear it because they live in a patriarcal society, where men call all the shots, and burka wearing, even if not forced, is one way of gaining male approval.
Either way, it represents an attitude toward women and womens bodies that is surely not acceptable in an era where we are at least striving for equality.
If such extreme modesty of dress were demanded of both men and women, then fine, its your religion, cover up if you must. ALL OF YOU COVER UP.
However, the minute a more stringent standard of modesty, dress and behaviour is demanded of one sex and not the other, then it is immediately unacceptable because it is straightforward sexual discrimination.
Objecting to that has nothing to do with sectarianism or racism, its an objection to a view of womens roles and womens bodies that that people have fought for a century to be rid of. Its like emancipation never happened and i do object to seeing the clock roled back in this country or any other modern democracy.
The day I see a muslim couple tripping down the road in matching burkas (rather than one a pair of jeans and a t shirt and one covered from head to toe), then I will accept it as religious practice and respect their piety. Until that day I will object to the burka and describe the wearing of it as what it is, subjugation.