This makes sense just by the nature of how people react and socialize at certain gatherings. Most people at restaurants sit down, eat their food across from each other, and move on fairly quickly with very little contact beyond their utensils, and food, and the conversation at their booth. Parties at halls, or other home gatherings are a much different scene ...People standing around a keg, or table of food, close to others, talking for long periods of time.
I have been back at my gym since it re-opened. I speak to the managers there every so often to get a sense of how the virus may be affecting the gym and patrons. I have been told that zero cases have been traced back to the gym. That in itself does not mean much, but is interesting just the same.