Back to the original question, "do I really need a license?"...the laws say Yes. Considering how easy and inexpensive it is to get licensed I don't understand why you wouldn't?
As Dave said, the amateur radio hobby is what you make it. I myself am licensed and hardly ever turn a radio on. It's my observation that you (and a group) essentially need to create situations in which to use amateur band radio. It's a just another tool to have in the toolbox for those few and far situations where it's capabilities make it the "right tool for the job".
I am not a big fan of ARRL, I think it is a dinosaur. I understand what they're trying to accomplish as a form of private regulatory organization but don't detect any vision or spirit of innovation. It's pretty hard to identify which decade or even century you're in when you deal with ARRL. For the sake of perpetuating the hobby and expanding participants, I'd like to see a shake up at ARRL. They just seem to be content to protect their mid 20th century view of the world and stand pat as though time is standing still. Hell, just look at their organization's logo...ever see anything more in need of a refresh?
All ranting about ARRL aside, it is the law to obtain a license to operate in specific frequencies. Just because the laws aren't aggressively enforced on individuals isn't a valid reason to disregard compliance. It's easy and cheap, why not just do it and be done with it?