I dunno, brewing is essentially cooking to begin with, there's no alcohol involved until after fermentation. If you provided a service where people were able to use your equipment for the cooking bit, and took the wort and yeast away to their own premises for fermentation it might be a different story.
You could then step it up a level and let them store THEIR alcohol on YOUR premises - like a friend leaving his beer in your fridge over the weekend say. If it's their beer to begin with, since they made it, how is the legal situation then. Tricky one I'd say - you might need the same sort of certification as say a cooking school would.