F-117's will often "stage" somewhere near an airshow or even fly from the airport where the show is held. When I was at the Tyndall AFB
show in 2002, an F-117 took off, made a pass or two, proceeded north about 200 miles to make some passes at another show, then returned--a B-1 did the same thing that day.
As for the B-2, very rarely will they park at a show--unless it's a really big show with proper security(i.e. the USAF
50th anniversary show at Nellis) Typically, they fly from Whiteman, make the pass, then fly home. I would assume they probably do some training as a part of the flight to help justify the expense.