Why do sellers block out, or 54XXXXXX the serial numbers of cameras they're selling?

Just curious as to why sellers either black out, or do the "54xxxx" thingy to the camera's serial number when selling their cameras?

I'm sure there's a logical explanation/reason that I'm going to feel stupid about when someone answers, but I just can't think of it right now.

I'm sorry if this has been answered before, I did a search and couldn't find an answer.

Also sorry if this is posted in the wrong section.

Same reason that people think that posting photographs of their children online is somehow dangerous.

I would guess it's so someone doesn't have an easy way of grabbing a legitimate serial number (for whatever purpose you could make up that it would be useful).

There are several reasons. One, you can use it to fraudulently file rebates (and receipts) or warranties, be it Canon or third party. Once they are registered it is a pain to prove you are the legitimate owner of it.

Two, you need serials to obtain access to the CPS program, and it would be easy to cheat the program and lift other's serials online.

ImCBParker wrote in post #9381504
There are several reasons. One, you can use it to fraudulently file rebates (and receipts) or warranties, be it Canon or third party. Once they are registered it is a pain to prove you are the legitimate owner of it.

Two, you need serials to obtain access to the CPS program, and it would be easy to cheat the program and lift other's serials online.

Sounds logical to me.

it only semi works since almost 100% of the time someone will give you the serial if you ask for it

Thanks for the answers.