The difference is (like always) consent.

I was about to ask a question but realizing my backlog is approaching 400, I'm afraid my shitpost question (are devil fruits even sentient?) having an actual major spoiler answer.

Quick rundown for people unfamiliar with the series: You get powers by eating devil fruits. They come in animal (e.g. jaguar man), elemental (e.g. sand man) and random shit (e.g. rubber man) variety.

You would think this is a dog that was made to eat the bazooka fruit.

This is a regular bazooka that, through the power of science, was made to eat the dog fruit, and is now an animate object.

So, answering your question: I'm really unsure about it, since they're (as far as I know) two entirely lifeless objects fused into a good boy that borfs rockets.