Ah, it looks like it is. Unlike most of the premium features on the site that have a green checkbox, that particular dropdown doesn't have one. If you hover over the dropdown though there is a tooltip popup that mentions it is a premium feature.
I had enabled the free trial a week or two ago and not realized it was a premium feature, now that the trial has expired I have a mismash of decks with and without it set.
Thanks for pointing that out.
-Travis