Size matters.
Whether your beer of choice has been canned or bottled, once you open that bad boy up, you'd better be determined to finish it. There's no way to properly reseal a Growler or Crowler for freshness. That considered, I don't know about you, but I'm much more confident in my ability to finish 32 ounces of say, some rare bourbon barrel aged ale, than a whole gallon. Sure, sharing is caring. But sometimes that's the last thing you want to do with your precious hand selected brew! And for those times, it sure is a waste to know that last pint or two will be flat and ruined tomorrow, primed for the drain no matter how tightly you screwed that cap back on.
Freshness matters.
Not only are we craft beer geeks concerned with how long that beer will stay fresh after it's opened, the shelf life of that freshly sealed brew-transporter is of utmost importance too! What if you decide to travel with your beer--you know, bring it home to meet the parents? Or save it for a special occasion?
First of all, glass has this habit of being, well, see-through--or should I just cut to the chase and call it "UV-ray-through?" Light exposure can start affecting the flavor of your brew in as little as a few hours, and even the dark brown glass most commonly used for Growlers will still not be as effective at protecting your beer as an aluminum can will.
The same holds true with fresh beer's other nemesis, oxygen. Any capped Growler will surely allow for some, however minimal, oxygen exposure even before being opened. That's why the typical shelf life for a "growled" beer is a week or less. The Crowler, on the other hand, is sealed tight by a machine that effectively folds & clamps the aluminum lid on top, ensuring no oxygen can go in or get out. Depending on where your beer gets crowled (some of the machines vary in oxygen purging & CO2 infusion capabilities), you've got yourself a fresh brew for anywhere from 2 to 6 weeks! Some will tell you longer, some will tell you shorter--but at The Craft Bar, we feel pretty confident saying 2-3 weeks. We pour it, seal it, sell it, buy it, and drink it...and that's the consensus.
You break it, you buy it.
The obvious point here is that glass is fragile, and aluminum is not. Not only is glass relatively easily broken, it poses potential health risk and danger once it is! For me, the idea of "to-go" represents freedom, fun, and frolick! Unfortunately, most beaches, parks, and other public areas prohibit glass altogether, thus limiting drinking destination possibilities with a Growler in tote. Alas! One more point for the Crowler, which is perfectly acceptable anywhere that allows the consumption of alcohol!
Because glass is reusable (albeit fragile) you pay extra for it. Your first Growler purchase will almost always include a "deposit," which is an investment in the glass jug itself, in addition to the beer you fill it with. Then, for however long you manage to keep it in one piece and properly sanitized, you can continue to fill it for only the price of the beer. Since Crowlers are disposable, you'll never be charged for anything other than 32 oz. of beer** and folks, that's what we like to call "bang for your buck!"
**The Craft Bar never charges a deposit/extra fees, but some other places might.