The most obvious is to exempt food and scrap the prebate. This way the government is not sending a $300 checks every month to every bum in this country keeping him supplied with wine and crack. Would save billions in administration costs.
Gotta be a better way than a prebate.
Alternatives
1) let Congress & lobbiests decide what to except from sales tax playing the same games the do today with income deductions and tax credits.
2) no rebate no exceptions in products and let liberals kill any chance of passage for taxing them poor folks.
3) require folks to track purchases and report them to the government to claim refunds or report household income to qualify for special treatment, issue tax exception cards etc. (keeping an IRS in family finances)
4) treat each citizen the same and rebate sales taxes by an an amount based on household size rather than qualifying by income or wealth.
5) Other, please specify your poison.
Try that with the current IRS and see how far you get.