There is a difference between someone choosing to wear a ski mask or helmet into a bank or petrol station, and someone wearing a burka because it is an essential part of their religious beliefs.
Asking someone to remove their optional face covering does not infringe their rights to express their religion. Forcing someone to remove their burka does.
If identifying the wearer of the burka is essential (as it sometimes is in airport immigration), they can do so by simply taking the wearer to a private place and having a female officer look under the veil. Handling it in this way, instead of a blanket ban on wearing burkas in banks or petrol stations, would preserve the wearer's right to their religious freedoms, without compromising the safety of bank employees.