Being in a place where so many people share a set of core values means you have the best possible chance of interacting-with and benefiting-from positive group-think with them. (I'm in no way saying that everyone at any given conference shares your core values — I'm merely suggesting that you'll experience a higher concentration of people who do at these events, than most other places.)
Tactically speaking …
I have three rules to help myself maximize the benefits of conferences/events (for those of you who know me well, you'll remember these as my 3 Rules of SXSW):
1. Let serendipity be your guide; she's a kind host
Think about it; when was the last time you let go, and just let serendipity guide you through an experience? Chances are you spend more time swimming against the stream that is your life than you do swimming with it. Letting go and letting serendipity take over gives you the opportunity to make the most of each experience and interaction. It also helps if you trust serendipity; that lets you trust that what you're currently experiencing is exactly what you're meant to experience, and hence, you're having the exact experience you need to have at any given moment.
This perspective allows you to make connections between problems and potential solutions that would be unattainable to your conscious mind.
2. If something makes you feel uncomfortable, do it.
That's the only way any of us can grow. As humans, we're absolute creatures of habit. And when we practice our habits, we're just reinforcing what we know. When we do something that makes us feel uncomfortable, we're doing something new, and doing new things helps us learn and grow. If you want to leave a conference or event feeling like you've transformed into a newer, better version of you, this is a must!
3. ABC — Always Be Charging
Your body, your mind, your devices (if they're required for attendance). If you're walking around letting your subconscious guide you, you're not going to notice how much you're draining yourself. If you have a chance, sit. If you see something that you feel will recharge your mind, do it. If you need your electronic device(s), when you see an outlet available where you are, charge it/them.
The Unspoken Rule
You need to surround yourself with people that get the above three rules. If you talk to people about the above three rules and they seem perplexed (like you just mentioned the unmentionable), you need to move on to someone that does understand. If you talk to someone that gives you a business card within the first 60 seconds of meeting, you need to move on. Try to have as many meaningful conversations as possible, because those are what you'll remember.