How dare you call it a DDoS. Pretty sure everyone involved is paying their internet bills.
(Disclaimer: I do not endorse DDoS, just pointing out the hypocrisy)
Uhm, usually DDoS is done via botnets so it's not the attackers that pay the internet bill but innocent people with malware on their machines. This means the attackers definitely do not pay for the full bandwidth that reaches the target.
So I don't think this analogy holds tbh.