First off, only starters went.
Ten wrestlers, three coaches, one trainer x $400 round trip = $5600
The average price to rent a large van is about $300/day.
Average hotel price in Corvallis near campus, 250/night x 7 rooms (two to a room) = $1750
Plus, your "3k for per diem" comes to $10,350. So, unless it takes them $15,000 dollars in gas to get from Portland to Corvallis, like i said, i question your comprehension of money.