Had a 2 day rental with budget out of DCA airport may 20th - 22nd, used the pay online feature and was charged 41.74 with taxes. After returning the car was hit with approx $8 fee for tax on ff miles. Is this normal, should this have appeared in the original charges since my skymiles number and bcd code were on there?

Anyone else get this charge, $8 on a $41 rental seems a bit high for a tax.