Actually it does, if you are a Wikipedia editor and have a photo you want to add their, you may not want to see it end up as someone's avatar on a dating site. However, if you click on any Wikipedia photo, you'll be taken to Wikipedia commons where the photo license information is generally clearly displayed. If you add a photo to Wikipedia content, make sure you also add the license information. You can add custom licenses to any photo that is yours through Creative commons. All Wikipedia photos are not public domain.