Circa 15 years ago when (most) states had no mechanism to tax Amazon purchases at checkout, and prior to it being flooded with made-up vaporware Chinese brands, Amazon had "good deals". They would usually beat retail stores in your area by 10-15% and they didn't have to charge sales tax.

Those days are long gone. You can't even be 100% certain the legit branded stuff you buy on Amazon isn't fake. (Unless they've recently taken new measures to avoid stock mixing and prevent that.)

Never has been tho, no vendor is gonna sell stuff at a loss. At best they're just reducing their profit margin.