I have to staff exhibit booths a few times a year. I absolutely hate that applicants treat it as a modeling job and send me their photos. My wife hates it too
I ask that they be capable of standing for 8 hours per day for three days straight, and that they be well dressed, well groomed, and personable. I will always hire the smart ones (you'd be surprised how many folks with a Masters or Ph.D. are looking for weekend work), and they rarely are the model folks.
I started putting "NO PHOTOS" in my ads a while back. I am thinking of asking folks to use a first initial and not indicate their gender, just to see what happens.