I was there Presidents' Day week last year (equally as crazy as any Spring Break week...remember that not all schools are off the same week for Spring Break) and it was only on one or two nights (only one while we were there), twice during the night.
We neither did the package (we never have and we've always seen the show whenever we were there and wanted to) nor did we stand in line for "hours" or even 90 minutes (again, never have stood in line for that long for it). We walked over before the first show as they were starting to let people in and got great seats about midway back in one of the center sections. Once settled, my dad went to get snacks for us since we'd had a big lunch and weren't really hungry.
We have always commented that we'd never do the package simply for the fact that those seats appear to be way over on the side and nowhere near as good as those you can get on your own.