Can iTunes gift cards not be used for Monthly Subscriptions

Is there a way for Monthly Subscriptions to not use Gift Cards?

I like to use itunes gift cards to purchase movies.

I like to keep a balance on the Gift Card for when good a deal shows up. The 4.99 movies are great.

The Monthly Subscriptions take away from my plan to use the Gift Cards for Movie deals.

Thank you with any help with this.