You can't expect everyone to memorize how to say "Reinheitsgebot" if they don't talk about German brews a lot.
Just because something is correct doesn't mean it's proper.
For example, with rare exception, it's not proper to correct someone's grammar in casual writing or conversation. You may be right about where to use an apostrophe, but it's rude to bring it up unless you're the offending person's editor.
Likewise in the craft beer world, you may have superior knowledge about certain things, but you have to be smart and delicate when bringing your acumen to the fore. With this in mind, here are five behaviors to avoid, unless mitigating circumstances say otherwise.
1) Correcting others' pronunciation of difficult beer names and terms.
Look, I'm a writer and I wish everyone knew all the rules of grammar, usage, and pronunciation, but even I make (plenty of) mistakes. So you can't expect everyone to memorize how to say "Reinheitsgebot" if they don't talk about German brews a lot. Likewise with yeast strains such as Brettanomyces, which is why even most brewers call it "Brett."
2) Whining about glassware.
Of course glassware can make a difference in how some beers taste, but not every bar is going to have the perfect glassware for every beer they serve. Deal with it. Be glad they are serving a beer you think needs special glassware. It's a craft beer evolution, not revolution.
3) Criticizing a brewery for getting too big.
This is a corollary to the indie rock fans who crab about bands selling out. To some people, Samuel Adams is no longer a legit craft brewer because of its large market share. That's crazy. Jim Koch is as committed to innovation as any brewer I know. This attitude isn't widespread, but I hear it enough for it to be irksome.
4) Complaining about the high cost of some brews.
Hey, guess what? Beer is not an essential product. If something is too pricey, don't buy it. If a bar is setting a price point too high compared to others when it comes to certain brews, go to the places with better prices. You're only complaining because it's a beer you want but don't want to pay what they're asking. If you didn't like it, you wouldn't care. So you have to make the choice. Is some beer too expensive? Yes. But it's a free market.
5) Expecting brews to remain exactly the same over time.
If you want this kind of consistency, drink Bud or Miller. They are almost perfectly consistent. Craft brewers are more at the mercy of hop crops and barley harvests. They may not have the same ingredients available from year to year. Plus, craft brewers are a iconoclastic bunch and like to experiment. I was guilty of this sin last year when I wrote a column asking Pretty Things Beer and Ale Project brewer Dann Paquette not to change the recipe for his near-perfect Meadowlark IPA. During a subsequent chat with Dann and his brilliant wife Martha at Sierra Grille one night, he gently informed me he might not be able to comply with my request. Why? He wasn't sure he'd have the same hops, but also, he wasn't totally happy with it (which is crazy–it was stellar). So I'll suck it up if he changes it this summer. I'm not lowering my expectations, though, just altering them.