I spent many years trying to get traction as an independent songwriter...doing the the "Nashville thing". The idea is the you want bands to perform your songs. The hope is that they will register the use of your song with ASCAP or BMI, so you can get something for it, should their use of it ever make money. Instead, you usually find some band that is just performing your song without having registered it anywhere. Total earnings = $0.
Another example: I used to do a songwriting blog. If you read through Songwriting for Dummies, 2nd Edition, you will see many excerpts from the articles I wrote. I am credited for a few of them, but many more were simply lifted directly from my blog posts, with no credit. I'm talking big segments...thousands of words. Total dollars earned = $0.
Another: many years ago I did a graphic of a rocker hand. Admittedly, it's pretty generic looking...it's a riff on the "men working" sign style. It's distinct because of the stud bracelet on the wrist. I see it all the time online. Total earnings = $0.
Another: My wife and I run a thing called Northwest Tribfest, which is a yearly tribute band festival here in the PNW. Last year we hired bands to replicate the lineup of the 80's Monsters of Rock lineup. We did a custom graphic of a dinosaur playing a guitar. Well...just last week we saw that somebody in LA is organizing a similar festival. Guess what their graphic was? Yup....stolen wholesale from us. Total earnings = $0.
On the last one, we sent them an email informing them that they were using copyrighted material without permission (which they surely already knew), and asking them to remove it immediately.....which they did. However, if they hadn't, what could we have done? Nothing. Total earnings = $0.