Better information about companies` behaviour, like the European parliament`s "fair tax kitemark", is clearly needed. When the USA faced similar problems of unpatriotic, greedy businesses during the 1930s, Roosevelt came up with "Blue Eagles", which, after a presidential explanation via a "fireside chat", companies could display in their advertising, provided their practice was in line with government policy. To encourage economic growth, and stimulate spending, decent wages, shorter working days and trade union recognition were all deemed essential. If something similar was adopted here, it would not not only provide much needed information for public consumption, and guidance before purchase, it would help provide a more even playing field for business, giving the more ethical companies a better chance of survival in the face of unfair competition from the tax avoiders and low wage payers.
That "handful of bad companies"which you mention, is fast becoming a "wheelbarrow-full", and the sooner action is taken, the better. With Osborne more often in cahoots with the City than not, few of us will be holding our breath!