I just found out that with some pretty simple google "hacks" it is very easy to find and filter thousands of unprotected mapfiles (*.vmt, *.map etc.), custom textures etc. I'm sure some of this stuff is for mods and by no means intented for public use.
When you store backups of your files on web servers only upload them on pw protectet servers/folders or at least within pw protected zips or rars if you dont want that everybody has access to it.