A parody is usually the same melody, but different lyrics. If I wrote the melody and lyrics, and you change just the lyrics, I would still get partial songwriting credit for that melody, and partial songwriting royalties.
Weird Al would still get full royalties for the performance part, but he would split the songwriting royalties with the original composer.
That’s why artists don’t mind Weird Al using their songs, because they make money. They like the validation, too, but they aren’t giving away their royalties to him so willingly for validation alone.
A parody is usually the same melody, but different lyrics. If I wrote the melody and lyrics, and you change just the lyrics, I would still get partial songwriting credit for that melody, and partial songwriting royalties.
Weird Al would still get full royalties for the performance part, but he would split the songwriting royalties with the original composer.
That’s why artists don’t mind Weird Al using their songs, because they make money. They like the validation, too, but they aren’t giving away their royalties to him so willingly for validation alone.