You can, however, move some via Hilton HHonors. You typically lose 70 percent of their value in the process (most exchanges first turn 5K airline miles into 10K HH points, then turn 10K HH points into 1.5K airline miles; airlines with programs that don't follow the usual North American mileage pattern have their own formulas) but it can be useful to "top up" for an award or if they'd otherwise be lost. Details at hhonors.com. Click HHonors Rewards on top, then Reward Exchange at the left.