Willy's Wonderland wasn't a great movie, but for me and my group of friends, it was a hell of a lot more entertaining than Mike and Jay are giving it credit for. While it could get repetitive (Nic kills an animatronic and then goes back to cleaning), part of what made it enjoyable to me was how Nic Cage was the most absurd part of an absurd movie. Doesn't say a word, dutifully cleans up the restaurant, throwing back energy drinks like they're going out of style...his bizarre performance carried the movie for us. The repetitive nature also lends itself to some running gags, like every time he beats up an animatronic and gets covered with oil, he immediately swaps his Willy's Wonderland shirt for a fresh one.
Honestly, I'm glad that there wasn't any deeper reason for Nic to be there (or at least not one explicitly stated), and I'm glad he didn't say a line for the entire movie. Both would have been a detriment in my opinion. I couldn't see a way to show the former without it being corny, and I was dreading towards the end that they'd throw in a one-liner to end the movie, which they thankfully didn't.
Oh, and with regards to the pinball thing, one of the last lines the owner says to Nic before leaving is that he should remember to take regular breaks. So Nic, in his autistic way, does exactly that, even bouncing before a fight starts to go take his mandated pinball time and leaving the girl to fend for herself until he gets back. So there was setup for that too, I'm guessing they just didn't pay attention because they were too busy imagining how little Nic cared about the movie (which I'm also not sure is fair, as I believe Nic's not in such serious debt anymore that he'll do anything for a paycheck so he can focus on projects he's interested in again; not sure if that's the case here or not).
Definitely some major plot holes (if one guy could beat up these robots so easily, why couldn't this town do the same, or just burn down the fucking place) and some instances of "this needs to happen because movie" (the character that doesn't want to go inside in the first place ends up losing a few IQ points to go fuck a girl in the party room), but I found it to be some good schlock. Certainly not the worst thing I've ever seen, and I doubt the same for either of them.
Might check out The Banana Splits Movie for shits and gigs, anyway.