Petition Tax 40% and 50% savings interest at source

Currently, additional savings interest for 40% and 50% tax payers above the standard 20% is being declared via tax returns wasting time for tax payers and costing the HMRC considerably in admin costs. Many PAYE tax payers choose to evade this process due to its complications and the agony of having to fill out a tax return for tiny returns for life. People who don't pay tax can simply fill out a R85 to exempt them from it, why can't there be a form for 40% and 50% tax payers to fill out to tax at source? This would raise revenue, prevent tax evasion, cut adminstration costs, save tax payer time. Win-win-win all round.