Local people are involved in domestic trips. These are the people who arrange for, and sometimes drive, the vehicles in the long motorcade that include local VIPs.
Hotel managers are involved because elevators need to be reserved, floors need to be blocked off, and room service has to be adapted to the needs of the White House staff and the travelling press.
If the President is speaking at an event, then the people who are in charge of the event have to be included as well as the managers of the venue.
The point is, a lot of people are not only brought into the process, but are thrilled to be a part of it.
I don't know what the Secret Service Agents that got sent home did or didn't do. I DO know that they are sworn to protect the life of the President (or anyone else they are assigned to) and I don't want that job.
They are, generally speaking, young men with guns in a foreign country. If they strayed and it had no effect on Presidential security, it is something less than a grave national issue.
Give them the equivalent of a Leroy Jethro Gibbs slap to the back of the head and send them back to work.