More like Oktoberfest. The Germans put up temporary "tents" (made of steel) to provide sheltered areas for eating and drinking.
There must have been some facility for storing large amounts of food and drink for the crowd. The well-kept houses might have been for the "priestbrewers":
Beer brewing ‘formed part of Neolithic ceremonies’
Without modern technology to build huge vats, only a few gallons of beer could be made at a time. Starting with the fall harvest, it could have taken months to brew the necessary amount. This perhaps explains the "Decemberfest" timing.
Preserving the beer against premature consumption would have required extraordinary measures: perhaps it was stored in a "sacred" location and access was only allowed during the solstice.