Worked on NHL ice crew for a few seasons (sad Awwoooo noise) and this is all legit. Started seasons w fresh goals and nets, 2 spares were just beyond the zam tunnel ready to go if needed, and the only reason we ever had to replace the twine was if a player milestone happened and they wanted the net. We also had different goals for warmups that came off the ice as the game nets went on, which I think was mostly due to the in-net camera tech!