2010-07-27 4-3 Answer

There are several reasons why it's best to hit here:

1.  Hitting is fun!
2.  Hitting takes away half your opponent's roll, and if you don't do that here, White is likely to make a good point on his side of the board.
3.  "Prime a point, hit a blot."  The best way to contain that last checker is to stop it from moving.  Also, if you get hit back that might help you establish a decent holding position on the other side of the board.

But the main reason it is right to hit here, and the main reason that MOST plays are right, is that they are better than the alternatives.  You don't always have the luxury of picking the most beautiful swan...sometimes it's a matter of not picking the ugliest duckling.