The stairs in the Apple stores are made almost entirely out of glass. There are no steel beams holding it up, the glass itself bears the load. The ones you usually see at high-end buildings/shops only have glass steps and/or sides. And don't forget the curved ones [1][2]. They are also earthquake-resistant for the japanese stores.

[1] http://www.macrumors.com/2012/02/29/stunning-photo-of-glass-...

[2] http://www.eckersleyocallaghan.com/projects/project/apple-sh...