The diagram says it all really...tints move towards white...shades move towards black!
The dark stockings is literally shading this models skin, making it darker to match the dress
Shadows in photograph also "shade" colours.
Tints are used commonly in annual reports, or in 2 colour print jobs as they create different levels of highlight but still in the one colour. If you used another colour to show the different columns in this table it would be too overpowering and the simplicity would suffer
Annual reports love to use tints.
Tints are very handy when designing large amounts of text, they help differentiate sections whilst still retaining the colour selection. Shades work well in this sense as well, but can be more dominating and doom and gloomy. Not as happy as tints!