Even if there is no one standing around him, as I understand it, you are shedding the virus even after you no longer have symptoms. So it lingers in the air and falls to the ground. That is why most people must test negative for covid to go back to work, which is often 30 more days. Their body is still producing the virus germs after they are no longer feeling sick.
If it were most of us, I think we would isolate in one room to prevent the whole place from having our covied germs, and limit our exposure to others at that time.
That is why he seems so reckless about other people's health.
His "motorcade drive by" was stupid. That the secret service had to be that close to him for that period of time, exposing them to the virus was un-called for. Now they need to isolate for the next two weeks. I am sure they will get the same care as the president if they get sick, because they are the secret service, but that sucks.
I think he did it for the world and his supporters to see he was still The President, and Nancy was not going to get her chance to be Commander in Chief. Many on the left were so excited thinking Pense would also go down with the Rona and Nancy would be their president, leading to AOC, Biden, and Kamala ruling the United Socialist States of America (USSA).