So a non-Jewish woman who has no connection to Judaism whatsoever should be barred from being a firefighter (assuming she can fulfill the requirements) because its unbecoming? Remember, we are talking about secular society rules, not Jewish ones here.
And I work for a union based company – should a union member who is female get an automatic lower pay rate because she is female? Everyone who joins at a certain position gets the exact same wage. Should they lower womens salaries?