Many people really enjoy going to concerts, I am among those people. However many people also don't really know what is the proper way to behave while attending a concert. This goes for both people attending concerts and photographers working at them.
As far as the photographers are concerned, a lot of really big tours have hired band photographers that work for the label that the band in signed under. They are paid to tour with the bands and take pictures of them all along the way so generally they know whats up, they know how to act because they are present for every show and they are typically pretty close with all the band members they are photographing. Free lance photographers that go to one, maybe two shows in one tour tend to be a little more cut throat because they need to get their shots and be on their way to their next job because that is how they earn a living.
While that is all understandable there are certain common courtesies that can and really should be practiced. When there are free lance photographers involved they are usually a few different people working for different companies so the competition to get the best photo can get a little dirty. I've seen professional photographers nudging each other out of the way to get the shot they are both aiming for. When that happens its not only distracting to a fan trying to enjoy the concert that they have paid to attend but it also (I imagine) is distracting to the person or people preforming. Don't fight over a shot, its rude and while you were fighting over one great shot you probably missed two or three other ones because you were too preoccupied with your chest match. Plus you don't want to have pictures that are almost exactly like the other photographer's, then its not special.
I also have witnessed a photographer, at the most recent concert I attended, standing off to the side of the stage between performances talking about how they didn't like the bands that were playing or the music they were playing. While everyone is entitled to their own opinion it is rather uncool and unprofessional to be talking about your dislike of the subject you're shooting while on the job. I, personally, would not want to sit through a One Direction concert but if I'm getting paid to take pictures at their concert I'm not going to walk around talking smack about them. Reason one being I wouldn't want to upset the crazy "directioners" for fear that they may kill me for speaking ill of the boys they idolize, and reason two being that its rude and unprofessional, when you are on the job be on the job.
It is understandable that when you are working at a show you are there to work, but there are people there that have paid to go and have a good time. Meaning that if a fan bumps into you or has gotten in your way it doesn't give you the right to be rude. If someone is in your way you can always go the normal person route and politely ask them to move. If someone bumps into you and causes you to miss a shot because your arm moved there is no need to turn and yell at them (also something I have seen happen.) The fact that people pay to attend the shows you are shooting at is the reason you are going to be paid for the photos you take. While I understand that fans can be annoying and get in the way they do help pay your salary or rate or whatever type of pay you are receiving for the photos you are taking.
Speaking of annoying fans these are some tips for people who enjoy attending concerts; by heeding these words of advice you, and everyone else in attendance, will probably have a better time are less likely to piss the people around you off (including the photographers).
-If you plan on crowd surfing don't wear boots. I have seen a kid get knocked out because some idiot decided to crowd surf while wearing work boots and this poor kid took a boot right in the temple and he went down. Wear sneakers or something light that won't fall off your feet. Also if you have a back pack with you leave it with someone who is not going to go crowd surfing. No one wants to be hit in the face by your back pack just like no one wants a boot in their face.
- If you are really tall stand in the back. No one can see over you and that's rude, I paid to see this concert I'd like to actually see it.
-If you start getting over heated because you are down on the floor and you feel there are too many people then just politely ask the people behind you to let you get out. They will be more than happy to take your spot. Don't ask the security people to pick you up and lift you out unless it is an emergency. They are hot and tired too. You have legs if you can use them then use them.
- Personally when I go to concerts I take a ton of pictures. It is understandable to want to have documented proof you went and pictures to reference for memory but please don't have your phone in the air the whole time you are there. Your arms and phones get in the way of the short people who already can't see because some six foot tall person is standing right in front of them (literally me every time I go to a show.)
-Don't aggressively shove people for no reason when you're on the floor. You are all packed in there like sardines, no one is going to be able to move forward so trying to force your way to the front isn't going to work. Also you could hurt someone, concert going is dangerous enough as it is no need to add to it with your impatience.