I remember asking on the Discord once since I thought about unsubscribing from myself and this girl once said "there's nothing wrong with loving yourself". If that sounds goofy... it isn't when you think about it. I think the fact that they even allow you to do it in the first place shows that you're proud of the work you make.
Also you have to keep in mind for collab efforts. It's as if the creator is giving props to the team with the heart/subscribe. Like "If this were made by someone else, I'd follow it".
That's my perspective on it lol.