DC-3 out of fuel.

Can anyone tell me why people think it is necessary to scratch their names in almost everything they see ? :-(
  • JDF 5607a
  • JDF 5610a
  • JDF 5611a
  • JDF 5618a
  • JDF 5619a
  • JDF 5622a
  • JDF 5623a
  • JDF 5625a
  • JDF 5626a
  • JDF 5632a
  • JDF 5614a