There's something warming and comforting (atleast, if viewed from a "dwarfish perspective") about a seemingly endless store of quality spirits, on an icy cold Winter's night. One can very easily put one's self into the situation of being at a subdued but steadfast party in an long-established inn, surrounded by heavy stones, the heat of blazing fire,s and the solidarity of friends and acquaintances-cum-friends-through-drink, as you huddle together, beating the savage, unmercifully cold night only a few steps away.
If we can suppose that dwarfs (atleast eventually) do feel some of the effects of alchohol that humans do, then a great, bottomless cask, in this curcumstance, may almost take on aspects of the spiritual hopefulness and fulfillment of a religious altar, allowing you to--if not truly touch the face of one's chosen Creator, atleast feel that Creation has real and concrete merit, and through imbibing the drink at hand, you have the option to, for a limited time-and admittedly not without sure and righteous punishment for "committed sin", for giving in to real, basic, human/dwarf weakness (itself bearing a strange comfort...), put yourself out a little ways out of your misery, to step aside from life a little ways, and drown your sorrows, maximize your joys.
The pendulum of that act, those "good times" does swing back around sharp, but that's the natural of pendulous cycles, and of life, and is unspokenly accepted, and most importantly, shared by your fellow travelers.
It's symbolic of the Universe giving you some small permission to be yourself--specifically your weaker, less In-Control self, and to know that you are not alone, that within that fragility, if sought out, can be found warmth, acceptance, a feeling that the playing field is temporarily leveled, and that here, amidst this bounty of esteemed and finely-crafted, but still naughty, drink, it's ok to let go, fall a little bit, and trust the world around you to catch you, when you really aren't up to catching yourself anymore.
I think that symbol, and those emotions, would be appropriate to a dwarf community, that it's an obvious counterweight to institutional religion, and that big casks (and the bigger the better, as a sign of communal pride, if nothing else) would really take off as a fad. Not without some controversy here and there, ofcourse, but that's part of the price, and part of the attraction.
I also think that dwarfs would often be in a better position than humans at picking themselves up again, not giving in to true alchoholism (or atleast slovenousness and self-destruction) quite as readily, if only because of the highly driven structure of both dwarf society and dwarf physiology. Too much alchohol would eventually get in the way of the higher purpose of "Great Usefulness" each dwarf craves. If they couldn't avoid committing themselves to the drink, the community certainly would notice this, and would ruthlessly take steps to prevent one "bad dwarf apple from ruining the bunch", via jailtime and hammering.
That doesn't mean there wouldn't be "dry drunks" and alchoholics who are still highly functional, around, but it should be rare to see a dwarf completely destroyed and perpetually wasted by drink. It just wouldn't be permitted or glorified in the way it can sometimes sadly be, in real life.