Not sure exactly how this compares to what is in place out here... I haven't researched it all that close... When I moved out here, it was nice to take home more of my paycheck each week, and not to have to worry about state filings... I can agree that the upper tier may not be pulling enough weight when strictly looking at sales taxes and grocery taxes, but I don't know that I agree it's a burden turning a grocery bill that would've cost $102 into one that costs $108, particularly given that take home income increases... It's possible you and I simply have different definitions of what a burden is...
It's about proportions, not absolute amounts. The poor pay a higher proportion of their income on groceries than the rich thus increasing those taxes affect them more. Yes, everyone would benefit from no income tax, but rich people would benefit proportionally more.
Simple example: 2 people pay $100 in groceries per month, one brings in $10,000 a month(person A), the other $1000 a month(person
. They both pay 8% in income taxes, 0 tax on groceries. A pays $800 in taxes, leaving $9200 to use on $100 worth of food - so they pay 1% of their income on food. B pays $80 in taxes, leaving $920 to use on $100 worth of food - they pay 10.8% of their income on food. Now remove the 8% income tax and convert that to groceries. Now A has $10000 to pay for $108 worth of food - 1.1% of their income. B now has $1000 to pay for $108 worth of food - 11.7% of their income. So rich person A spends .1% more for food while poor person B spends .9% more for food. They both have more money regardless(by not paying income taxes) but that's not the point.