At a carnival party in Germany with 350 guests, more than 40 were infected by a single guest. That gives an idea how well it spreads in enclosed spaces. You can assume there was somewhat close contact, but I've been to business meetings with also at least 5-10 people <6ft from me. That's how it can spread through a company within days.
I have not been to carnival parties for 20 odd years, but as I remember them (in NL/border with DE), everyone is drunk, hugging, kissing (often on the mouth with perfect strangers), vomiting, not washing hands after toilet (is there a toilet even??), falling over each other and also having sex. Maybe times have changed, but if it still is remotely like that I can definitely see someone infecting 40+ other people.
I mean, we have city parties here 'for all the family' which result in everyone touching each other (just as friends mostly of course but still touching hands, shoulders, neck, face, back), kissing (mostly on cheeks with strangers, but you mostly 'friendly' kiss everyone meet/talk/dance with and otherwise shake hands or even both) but all the other factors do apply as well; bad/no toilets, no soap/water, everyone drunk so who washes their hands anyway, vomiting and not being so careful with putting your sleeve in front of your face when you sneeze or cough... I only go during the day to such things if I go at all (when most people can still walk up straight) because it is rather disgusting after a while (I am old; I used to like that when I was young), but I can see a few people infecting basically everyone if they are popular/drunk enough.
