Comcast XFINITY → Re: Why is there a second modem on my account?

What in hell are you talking about? How is having a non-existent modem assigned to your Comcast HSI account equivalent to having a "spare Internet connection"?

OTOH, if Comcast decides that the non-existent modem actually belongs to them when you terminate your account, who do you think is going to pay for it when you can't return it (or prove that it is/was your property)? Comcast has a history of claiming ownership of their customer's modems; getting a modem that you no longer possess (or possibly never had) removed from your account is just common sense given Comcast's history.

You clearly don't know how this can be used.

But w/e lol

Ofc it's too late for him to take advantage of it.

Apparently we don't.

Could you enlighten us how it can be used if he does not have the physical equipment?

Enlightenment is not JigglyWiggly's M.O.