They can afford more and they do pay more, that's the point. There's far too much conflation in most peoples minds between the ludicrously rich oligarch types or those with huge amounts of off shore wealth who are avoiding paying large amounts of taxation, and those who are normal PAYE employees on good salaries who are already paying their fair share (and proportionally more than most). People are forever using the example of the former to argue for further punishment of the latter through higher taxation, when they are not the problem.