ok sorry i see your questions went mostly unanswered. i know you're not playing yet so will answer them.
"first off does every camp do behest?"
yes, almost all camps do have behests including most of the indivicual nodes. some do not, but they are not low level areas at all. i'll use camp riversmeet for example does not but it's all lvl 50-75 mobs.
"Also years to come party grinding will be better."
yes, they will be better, but even when the game had alot of members they still did the same thing
"one of the bigger issues is no one is teaching anyone about anything."
not exactly true. i see some pure rude people sure, but the majority of the people i have met are pretty decent and will always give advice.
the reason people get upset about people way too low or too high is that they hurt the sp gained not just for that person, but everyone in the party. se has it set to where if the group is outside of a 5 lvl range they all take a sp hit on each kill. it's not as much for the middle people, but it is there.
sorry don't mean it if i come across as rude or elitest, but wanted to give the reasons why people do not like the leeches. the problem is the camp for the lower range actually gets passed by to get to the higher camps. those people pass by to go do it on purpose.