I-82 Rest Stop at Prosser Closed for Bomb Scare – Why??

Just read this story at the Tri-City Herald:

UPDATE: I-82 rest stop at Prosser reopened after package examined

PROSSER –

A suspicious package that prompted the closure of an rest stop just off Interstate 82 in Prosser has been examined and the rest area has been re-opened.

The rest area was closed for about 3 1/2 hours after state Department of Transportation workers found the package, officials said.

Washington State Patrol Sgt. Ed McAvoy said the workers found a plastic bag and thought something might have been inside the bag.

Troopers closed the rest area around 1 p.m., temporarily blocking both the entrance and exit driveways while a bomb squad from Walla Walla responded to inspect the package, said Mike Westbay, DOT spokesman.

Traffic on I-82 was not affected.

The rest area was re-opened at 4:30 p.m.

Are these bomb scares done just to give the bomb squads some practice? I mean a plastic bag is found at a Prosser rest stop and a bomb squad has to come from Walla Walla?
I could see if it was a bag hanging off the door knob of city hall. But are rest areas a high threat area? Have we just become paranoid?