I would suggest you always try to put yourself in the other person's shoes. How would you feel if someone ripped off material that you considered proprietary? Be honest with yourself about each situation and let your moral compass guide you. When it comes to YouTube tutorials I believe these are fair game. The creator of the video is being paid per view and also for any ads being played. But the main purpose of YouTube videos is self promotion. For example non blueprint Angela Walters machine quilting videos.....free, no ads....but promoting her personal brand and products (rulers for example). For myself her videos have helped me quite a bit and so I made a point of purchasing one of her books and a couple of her rulers. Being a former business owner maybe I look at things in a different light.