While the debate between balls and RNG is a legitimate one, the bigger area of potential abuse, that's rarely mentioned, is instant tickets. For many lotteries, instant ticket sales now generates the majority of revenue. Often exceeding the sales of all numbers games, including Mega Millions and Powerball, combined.
As for programming balls, that's not as crazy as it sounds. Some lotteries use balls that contain RFID chips in them. While that shouldn't matter, in theory, it could be used as another way to rig a drawing without tampering with the balls at all...
For example, one could tamper with the machine itself, such as adding some mechanism that reads the RFID signatures and only allows pre-selected balls to exit (or not exit) the chute. This would be very difficult to pull off, since machines are also inspected. However, it could catch some inspectors, who may be overly focused on the balls themselves, off guard.
Another method that wouldn't involve the machine nor the balls directly, though seems so far-fetched to be practical, would be to read the RFID balls at a distance, than use a powerful invisible laser (or some other remote method) to slightly alter which balls exit (or not exit) the chute. But I digress. Point is that even the balls themselves may interact with software.
Personally, my biggest concern when it comes to abuse is with instant tickets. Even more so for lotteries with a checkered past (ie. sometimes not paying out winners due to budget problems) along with those that are privately managed, which increasingly many are.
