The Spring Fairy image is a vector image offered at istockphoto.com. There are others by the same artist/contributor available. I got my hand slapped by them when they revised their usage terms many months back.
Even if you are not selling the templates, but merely “giving them away,” no images or other resources from istockphoto.com can be used in a distributed template. They can of course be used for a one of a kind design, which is I believe is what the designer is offering for the $30. $30 is not a lot of money to charge to rework a template.
If you strike out on your own to design and distribute WordPress themes (or any other templates or designs to be distributed to the public at large), be very careful where you download from. Not all stock image groups permit them for use in templates; and in fact, I believe only a handful do. StockXchange (https://www.sxc.hu) is the only one I can think of off the top of my head that permits this.
I posted an exhaustive list of image repositories awhile back. Search under LESSON if you wish to find it.