I am well aware of the difference between a Burka and a Hijab. I used the term "head wear' in a generic sense. But it is obvious you missed the entire point, The Hijab and Burka are both protected under religious freedom sections of the Charter, a Helmet is not. Hence they can ask that you remove your helmet, whereas they can not ask a person to remove a Burka or Hijab. Just as a person, (which I don't agree with may wear a Burka when being photographed for the drivers licence, you can not wear a helmet).
Which is why the OP making mention of the woman not being asked to remove her Burka, is not applicable, one is protected under law the other isn't. A shop owner can refuse to provide you service if your wearing a helmet, they can not refuse someone wearing a Burka, (without a media crap storm and even a visit from a human rights investigator)..lol
In the end as I said to the OP, it their choice to remove the helmet or give his business to a station without the policy. In the end it takes all of perhaps 2 minutes to remove and put the helmet back on, for me not a huge stumbling block.