I reckon Boggart-made sour milk would be alcoholic. Maybe with a brewing reaction that turns milk into alcohol.
EDIT: Some ideas for Wee Folk.
Gully Dwarves, inspired by the Gully Dwarves from the Dragonlance setting from Dungeons and Dragons.
Despite their name, their stature and their beards, Gully Dwarves are not 'true' Dwarves. They're said to be a cross between Gnomes and Dwarves, or Gnomes and Humans. Whatever the case, Gully Dwarves are far separated from the fortress dwelling, metal smelting, beer drinking Dwarves we know. Gully Dwarves can be summarized in a single word: poverty. Gully Dwarves live in tribal communities situated within ruins, swamps and caves. They wear disheveled, ancient clothing passed down generation from generation. Gully Dwarves value tradition, merriment, hard work, family and peace above all else. They despise law and decorum. They will gladly eat sapient creatures, make trophies of all creatures, and steal from one another. However, they despise murder, torture, lying and oath-breaking. Only the smartest of Gully Dwarves can count higher than one, and those who can do so are regarded as wizards in Gully Dwarf culture. Gully Dwarves are known for sending thieves to fortresses to steal, much like Kobolds. Gully Dwarves have no gods, and instead worship their ancestors. Gully Dwarves use wooden clubs and thrown rocks as weapons. Despite their poverty, stupidity, lack of metal and their criminal proclivities, Gully Dwarves manage to survive due to their high fertility and their relatively short childhood. Gully wives are able to produce litters of four to eight children, children who mature at the age of eight.
Floresiensans, inspired partly by homo floresiensis.
Floresiensans are violent, Dwarf-height tribal people who live in tropical locations. They value martial prowess, family, tradition, cooperation, and nature. They despise peace above all. They allow all things, from murder to cannibalism. Floresiensans use wooden, stone and bone javelins, axes, spears and clubs as their weapons. They are known for having domestic orangutans, chimpanzees, gibbons and other primates. In addition, they breed a special species of primate. Arborpithecii are tame, semi-intelligent apes which the Floresiensans use as work and war animals. An adult arborpithecus stands at the same height as a Dwarven child, but possesses the strength of an ox.
