Mine had 7 miles on it. Full of gas. I would expect a few miles and would not worry about 34 miles - as long as they started your warranty at 34 miles! If your truck was ordered I would expect fewer miles. Delivery was probably 2-7, then add a few miles for the tech to take a shake down cruise. If your truck was from the lot I would say its pretty normal.
The 3/4 tank of gas is more of a customer service issue than what you paid for. I would let the dealer GM know you are disappointed in not receiving a full tank. If they don't do anything to make you happy I would be looking for another dealer for my service and next vehicle. My guess is the GM will go out of his way to make you happy.
Good luck and enjoy your truck.