Why use infantry AT weapons?

[Blackcloud6]

Why would you want to use infantry AT weapons in an assault? You only have a 50% chance of using them and you could could end up doing nothing if you don't make the roll.  Then your chances of killing are low.  Why not take the normal assault value, especially if you have more than one unit and a leader present?

It might have been better if those units with infantry AT weapons got a +1 column on the assault table when fighting against tanks.