This is a bit confusing, but basically have you ever noticed how some sometimes better movies feel like they ripped off the plot of a movie, only to find out it came out earlier?
For instance, Mexican Santa Claus, the three kids who want to kidnap santa claus and stuff him in a bag, and the way those creepy reindeer move feel like it may have inspired parts of Nightmare before Christmas
and of course Zombie Nightmare is basically I know What You Did Last Summer (at least in terms of Plot),
what are some other cases where a cheesy movie has an idea that a better well known movie did better
I would argue that Night of the Blood Beast is a small-scale version of It Conquered the World, while Terror from the Year 5000 is a time travel variant on the same.