There is a lot more involved in sending out paper invoices than you may think. The real costs are actually higher due to many extra steps involved in also receiving and processing paper checks.
Cost of sending the paper bill:
Cost of envelope $.08
Cost of custom return envelope $.15
Cost of paper for invoice $.05
Cost of toner for invoice $.05
Cost of stamp $.49
Cost of labor to stuff and seal envelope $.50 (2 min at $15 per hour)
Cost of receiving paper bill and check:
Cost of labor to open envelope and manually enter check payment information into billing system $.75 (3 min)
Cost of labor to copy all checks for weekly deposit $ ~.05
Cost to drive and wait in line at bank to make deposit $ ~.20
Cost of $.20 each check bank charges us to receive the volume of checks we deposit. $.20
Cost of human error and having to track down incorrectly entered informaion $???
This shows we are losing money on the transaction. This is shown just to help people understand the many facets involved and why companies charge for paper invoices and to receive checks. I hope this helps you feel better about where the $2 is going.