A round baler gets up there too while baling stalks.  At $4/bale depreciation, $2/bale for net, $0.35/bale for fuel, $2.00/bale for repairs (teeth, belts, chains), and $1/bale for tractor at $9.35/bale in costs before labor, interest, insurance at 50 bale/hr you are looking at an operating cost of $467.50 so easily runs $500/hr while baling with no other support equipment.  Cost per hour of operation relative to new machine cost is way higher than most machines.