Broken glass, and Caltrop Puncture Vine are two serious sources of punctures for cyclists. 

Glass fragments on path by bus-shelter, Fremantle, just south-west of Traffic Bridge

Deposits on bottles will greatly improve cycling.

A major problem for cyclists, both regular and occasional is the serious prevelance of broken glass on our roads and bike-paths.

Firstly, this causes punctures.  Regular cyclists carry a spare tube, tyre levers and a pump, so a puncture is a bloody nuisance and delays the trip.  Many less regular cyclists probably neither know exactly how to repair a puncture, nor have the necessary gear with them.  Punctures from broken glass will be a major reason why some people give up bicycle use.  The extra environmental, health and oil vulnerability problems caused "lapsed cyclists" are very considerable in both economic and social terms.
Secondly, the patches of glass fragments on roads create serious safety risks.  Cyclists have to concentrate on the details of the road surface just ahead, and this can partly distract them for watching for vehicles and other hazards.  A cyclist suddenly confronted with a patch of glass fragments ahead by the side of the road will probably swerve out around the glass; risky if there is a car passing. 
The WA is the first State in Australia to be following the lead of South Australia which has had successful container deposit legislation, CDL, (initially 5 cents per bottle or can, now 10c) since 1975.   Anecdotal evidence suggests South Australia has much less broken glass on its roads.
However, there is a lot of opposition from the packaging industry, who want the costs of litter and landfill to be borne by the community as a whole, not by those who manufacture the containers or those who discard them.

Cyclists and bikeshops should get involved, by writing to their local member of State Parliament, or ringing to register their support.  We should also contact our local councils and bicycle clubs to make sure our views are heard.   There is far too much broken glass around, and CDL will make a big difference.  As it is only glass containers lacerate kids' feet and punctures, there is a good case for a CDL system which favours cans, plastic and cardboard containers, which do not shatter into razor-sharp fragments when dropped or run over by cars.