The money is taken at the wellhead.  At first sale.  If a dollar worth of oil is pulled out of the ground a percentage of value is taken.  The percentage determined by a citizens assembly.  After that the cost is simply passed on as markup in the distribution chain. 

The money is equally distributed and kids get a percentage starting at 16.  Younger kids don't use gasoline or diesel, and the money needs go to people who use oil products.  Young kids are excluded.  They do not buy anything.

The users of oil products need to use their part of the payout to offset the extra cost that must be passed on after collecting the dividend.  The point of the dividend is to compensate the average user for now more expensive gasoline or whatever carbon product they are addicted to.  If everyone used the same amount of carbon, carbon dividends would do absolutely nothing.

But some people use more fossil fuel products than others do.  Those who use more wind up giving money to people who use less.  That is the whole point of carbon dividends, and why money should not be given to citizens too young to drive.  Age 16 makes sense for a lot of reasons as the starting age.  Younger kids use fossil fuel products, but adults pay for them.

It is essential that all the money collected be equally distributed.  The point is to make carbon dividends invisible to the average user.  But those who use more fossil fuel products than average will pay more because they use more.  People who use less than average essentially get a small UBI.

The barista who only rides the bus makes bank.  She only pays a slightly higher bus fare. 

Homeless people get the most money from Carbon Dividends.  Maybe enough to keep them fed and in a good tent.  A lot better than the fuck all they get now.