Carina from Polka and Bloom is doing a series on watermarks. She started off with Four Reasons You Should Use Watermarks and is continuing with a how-to and I recommend you read it. (If you love Europe, color or embroidery, you should be reading her blog anyway, BTW)
I have mixed feelings about watermarks.
On one hand, I'm lazy. Well, not so much lazy as non-industrious about it.
Photography isn't my business. It's a nice hobby, but so far absolutely none of my images have ever made me any money. I haven't figured out how to make that happen yet. And since I quit making crafty stuff to sell, none of my images are depicting anything that is making me money either. So if someone steals my picture, it's not really causing my wallet any damage.
I know, not a good attitude and I agree.
When I make an image with a watermark, I have to save two copies. I like having clean media storage, and having two copies of one thing seems excessive and cluttery to me. And quite a hassle, since as I said a second ago, those binary digits don't make me money.
Stealing someone's images is BAD.
This means saving the file and then later representing it as your own.
This means posting it linking back to my image where it is stored and also stealing bandwidth.
This means pinning or blogging without a correct link or mention of the original source. (I can't claim to be perfect on this one on Pinterest, but I do try to make sure the link is right.)
Images are the new internet currency, I get that, but it only takes ten seconds to state where you found that picture, really. Pinterest even will do it automatically if you click "create pin" and put in the page address where the photo is.
The site is in a language I can't read (which also conveniently won't translate every time I try), so I can't tell if their intent was good or not. But it doesn't matter. There is no mention of my web address or my name or anything about that post at all. I put the effort into making the item and writing up a tutorial (to be nice and help out other non-traditional/crafty brides), and none of my effort was represented there. NOT COOL. Just because someone give you free instructions on how to do something doesn't mean that you have free reign to just eliminate them completely when you tell the rest of the world about it.
Needless to say, the originals got deleted (and do not show up on that site anymore), and then those images got branded and reloaded.
I won't put watermarks on every single thing I post, but I'm probably going to go back and do that for all my tutorials, because people apparently can't be trusted, even in the craft community. Just another thing to add to my "reasons humanity sucks" list.
Long story short: Give the creator of something their rightful credit.