Even if they cannot bunt, make them spend time in the cage doing a controlled half swing to put the ball away from the shift. With enough practice, there should not be a single MLB player that could not do that. On the other hand, the bunt is a different animal, as players can get mental blocks, worried about their fingers or if the ball is coming right at them. The controlled half swing avoids those issues and is just as effective, if not slightly more, as it could very well give the players using that against the shift some doubles on top of the singles with the batted balls getting just out of the infield.
"Always look on the bright side of life!"
Eric Idle