I know exactly what you mean. Mf's got 12 pair of retros from post 2012 and claim they are "sneakerheads." I would consider myself a sneakerhead but would NEVER refer to myself as one. I mean I love sneakers, I have a various selection, spend most of my money when I shouldn't on sneakers, skip meals sometimes to make sure I have the funds for a new release, frequent sneaker blogs, make sure I know my history of the things i'm wearing and even spend a good amount of time posting on NT. But with all that said... if someone asked if I were a sneakerhead I would simply reply "idk man I just love sneakers"
There def are some girls in my area that would claim they are "sneakerheads" but they fall into the same category with the dudes with J's. And you're totally right... they are just trying to impress the lame dudes. I have yet to meet a female with a respectable collection. Except maybe a few chicks I used to work with at Finish Line back in the day.
Most of the females I have seen with the best collections are on IG and they come from the UK or Europe