I believe it did poorly because it just wasn't a good movie. Poor direction, poor and predictable story line, and the acting was something you would expect from a B movie, at best. Our boy is clearly better suited for music, and music videos ... to carry an entire movie just isn't his forte. I've watched the movie a few times, and it's just not one of my favorites ... too slow paced and it gets boring after the opening Indiana Jones sequence. Even Richards couldn't save it. I think that's why it didn't do all that well at the box office.
There. I said my peace. Let the stones fly.

(with all that said, am I glad to have it in my DVD collection? YOU BET I AM!! It is Al after all!!)