No. My policy with another insurer was expiring and I wanted to make sure there was no gap in coverage but they were unable to process my application quick enough or communicate effectively about the time it was taking. So I ended up just renewing my policy with my original insurance company.
There is officially no charge for the residency letter so they can't give a receipt. It doesn't open the door to corruption. It is corruption. For visa fees, if they are charging the proper fee, they will always give a receipt.