Buying a month pass is a tax benefited account for commuting. [At many work places]. On top of that you have different pricing and you aren't paying full price

Buying a month pass is a tax benefited account for commuting. [At many work places]. On top of that you have different pricing and you aren't paying full price at tap. The CC being picked up means you're paying the full fare immediently even if you have the pass on the other card.