I'd be curious to see what the epidemiological modeling would actually show about this. Imagine a scenario where high risk individuals remain at home while all low risk people in the country who aren't essential employees interact with and only with their nuclear families and a consistent group of seven other people along with maybe the minimal amount of stranger contacts necessary for each family to send someone to the grocery store every 7-10 days.
I'm not an epidemiologist or a stochastic modeler, but I do suspect that if every single low-risk person with a non-essential job did exactly as these boys are doing, this would be enough to "flatten the curve." I think the real problem comes from people congregating in large groups or continuing a lifestyle that involves regular interaction with strangers (interacting with 7 unique contacts per day is way worse than running with the same 7 guys every day from a transmission standpoint).