I guess, like anything else, all bamboo flooring is not created equally. There are thousands of types of bamboo and I'm sure some are better suited than others.
Here's a link to one that claims to sell very hard flooring:
http://www.bamboofloorings.com/bambooflooring/faq/index.htm
How hard is your bamboo flooring?
When tested according to the standards of the National Wood Flooring Association Test (Janka Ball Hardness Test), it shows an average hardness of 1320 PSI comparing with the northern red oak. The carbonization process reduces the result to 1010 PSI, the strength of walnut.