They probably both offer some value by packaging existing ideas in more palatable ways. If you don't mind the motivations and style (like I do) you can probably extract some benefit. It's just not for me.
Reply to your edit: You must not be aware of how much money conferences can make to not see the profit motive there. Even moderately successful tech conferences can generate millions per year. Far better than a consulting business. It takes time to build up to that of course. Publishing a book is Conference Building 101.