At present, people in poverty, and well above the poverty level, pay no federal income taxes. They do, however, when employed, pay payroll taxes, sales taxes, and other regressive levies at federal and local levels. So your purported 'fix' to this national sales tax does not improve matters. By structuring it as a refund, whether monthly or quarterly or annually, you require payment first, which will tend to reduce consumption, and raise the immediate cost of necessities for the less well-off. The end result will be that people who are at the poorer end will have less spending power.

Federal 'hidden taxes' barely exist; the effective federal tax on corporate profits runs at less than fifteen percent, with many business paying nothing, or even receiving payment from the government in accordance with various refundable credits. Note the tax is on business profits, before you run off on the assumption one sixth of prices reflect taxes: business profits run on average between five percent and fifteen percent, so you are speaking of between one and two percent of gross receipts reflecting collection of taxes from consumers. The chief increase in 'prices' owing to federal taxes are the openly stated excise taxes, and the payroll tax, which is a wholly regressive levy, and designedly so. These things, in effect existing consumption taxes levied against the wages of working people, are not addressed by your proposal.

Touting as an advantage that purchase of second-hand goods would be exempt is risible, but does open a window into one of the real motivations behind these 'consumption tax' proposals, which is a feeling that the poorer and less well off spend too much on themselves, try and have more than they deserve, and to live more like their betters. In earlier times, these feelings issued openly in sumptuary laws, which forbid people whose income was below certain levels from purchasing certain items, or wearing certain articles of clothing. It is odd how people who continually chant, when it comes to investment and business activity, that to tax something is to reduce its supply or frequency, turn around and deny that taxing consumption would reduce the amount of consumption in society.

The great favoritism in the tax codes, before which all others pale, is the taxing of income from appreciation of capital assets at a much lesser rate than the rates at which taxes are levied on wage income, and the exemption of the sale of financial instruments from any sales or excise tax at all.