I'm a 23 yo student, and I always travel in economy. I dress normaly, with jeans, but on the other hand I have long hair

I can't say I have problems, except for requests at check-in (like seat row), but that depends: sometimes I request "as much to the front of the plane as possible" and get a "yeah right" look and a seat in last-five rows, other times I get my request fullfiled and smiles... once I was even upgraded in one segment even not having status with the airline (LH), and had no problems whatsoever in seating in 1F.

Let me just add that I fly in average every 1.5 months almost always with Lufthansa, but only within europe so although I get close I never got status with them.

Pedro