I see it both ways. As a creator, having spent a lot of time and effort on a project, only to have someone else share it and reap the rewards of my time, can be frustrating. Even if they have a big following and I have a small one, the amount of effort vs reward in them sharing my content vs me creating it can be a great divide.
On the other hand, a following doesnt grow overnight, and a curator can spend a long time establishing themselves as "someone who finds gold" and therefore gather a following. So long as you always give credit to the author it's usually fine, but there can be instances where the original artist is completely overlooked as something that just earns the curator money. As an artist, I dont work for you, you dont pay me and I didnt hire you, for you to be profiting off of me can be seen as at the very least intrusive, at worst downright insulting, which gives the feeling of theft.
Please note I'm not accusing you directly, just curators in general. I've been on both sides of the fence and it can be a touchy subject for many, but thanks for taking the time to bring it up, it's always a good discussion to have. Curators have a place, but content creators should be reimbursed as well. Steemit does a decent job of this for those of us who post on this platform, but if you posted everything from youtube here without the youtuber's consent, it could potentially be considered a copyright infringement if you began profiting off of their content in a significant manner.