The lack of sidelight use is a result of both changes in lighting technology and the habits of drivers. The vast majority of modern cars have both daytime running lights as well as an automatic lighting function, and while the specific operation of automatic lights will vary from manufacturer to manufacturer, a significant majority will automatically switch from DRLs to full headlights with no provision for the use of sidelights. It is also fair to assume that many drivers either rely completely on the automatic function of their lights or simply switch to dipped headlights when they deem it is dark enough. Better use of sidelights would be advantageous for all road users, but this would required a change in attitude and awareness of drivers, which one might argue is already in short supply...