The code I use is from my husbands former employer. However, it used to be called a “friends and family“ discount. I am not seeing that language anymore.
the rate is currently providing a savings of almost 65% so given current circumstances I’m not going to stop using it. I also don’t share the view that this is somehow theft.
Regarding insurance issues, I don’t see how my insurance company or even credit card would be made aware of the code that was used. It would not be in the rental companies interest to prevent an insurer from paying. I also think it would be difficult for an insurance company to ultimately deny the claim based on this discount code used.