All somewhat true, but there are a few key areas where America does attend mass events that can help spread diseases quickly. The top three examples in my mind are the trifecta of public schools, large office complexes, and churches (esp mega-churches).
These all feed and overlap each other. Something can spread through the public school system's children quickly into parents, who take it into large shared office building environments (think typical complex of skyscrapers full of tenant companies sharing hallways, elevators, sidewalks, lunch spots, etc), and once a week completely different insersectional sets of these adults and children then gather up in a large church and disperse into the trifecta.
Hospitals themselves are another factor. Those with family ties end up randomly visiting hospitals a few times a year on average for their eldery relatives' or childrens' sakes, where they pick up a ton of chances at diseases.
During a serious outbreak of something more transmissible than endemic disease like the flu (and all the various viruses that give us colds), people would freak out and attendance to all those things would plummet.
These all feed and overlap each other. Something can spread through the public school system's children quickly into parents, who take it into large shared office building environments (think typical complex of skyscrapers full of tenant companies sharing hallways, elevators, sidewalks, lunch spots, etc), and once a week completely different insersectional sets of these adults and children then gather up in a large church and disperse into the trifecta.
Hospitals themselves are another factor. Those with family ties end up randomly visiting hospitals a few times a year on average for their eldery relatives' or childrens' sakes, where they pick up a ton of chances at diseases.