We already have sales tax!!
So many fares calling for a tax on sales. We already have one, it's called VAT and is applied to most non essential items at 20%.
Every new piece of hardware attracts VAT that the retailer collects from the consumer and pays to tax authority minus a percentage for the trouble of collecting it.
A £1200 laptop is actually £1000 + £200 VAT. Apple probably wholesale the laptop to pc world at £800, allegedly making ~30% so costs them ~£600. that £200 between wholesale and resale has to account for marketing, staff, stores, etc leaving a little for profit to of world.
The tax authority is by far the biggest earner of the lot, earning a huge 20% after everyone else has whacked in their costs and profit margin on the actual wholesale cost plus earning a percentage of each member of the chains profits, for essentially permitting the product to be sold in their area.
We consumers end up paying almost double the price the manufacturer sells the product into the channel for, especially when you consider we pay for goods and vat out of already taxed income, I.e you have to earn more than £1200 in order to take home £1200.
I'm not seeking to justify tax avoidance, but tax isn't simple or clear cut, lots of compounding and the tax man always takes the most.