I don't see fire fighters or policemen or construction staff, so her statement (and other peoples argument) is valid. How to interpret this fact can be tricky, because there's still more variety than traditional 'girly' toys I think, but when contrasting this with the "City" line of toys (http://www.lego.com/en-us/city), the gender bias is blinding.
I think it is great that Lego has developed a theme that isn't focused on physical confrontation. I have three girls who play with Lego and they request a mix of sets. For Christmas, they requested sets from Friends, Lord of the Rings, and Ninjago. My four year old got a Chima set. They don't see it as a girl vs boy thing.
Now, if I was heavily into buying Lego bricks, I'd also mix from the different sets to have more situations, and my kid doesn't really care if his toys are action figures or dolls.
You know what "traditional" girl toys are? What previous generations, or "parents", say they are.
Please show me what makes the actual firefighters and policemen "male"? I see some figurines with beards, but many without beards - they could be any gender.
Also never mind the fact that including many female fire fighters would be a lie, because the real world isn't really like that.