I believe you. However the current sign is very much single use, with the opponent, date and time printed each time, and slotted into one big slot.
Agree that this is not a big cost, but at the very least it'd be more sustainable to change the main sign to have a slot for opponent, a slot for date and a slot for time, and use reusable signs with opponents/dates/times on it. The opponents, dates and times are quite predictable anyway, so I don't think it'd be too much of a hardship to make and store.
The hierarchy of sustainability is reduce/reuse/recycle so if it can be moved to the reuse instead of maybe recycling depending on material, I think that'd be a positive and sensible move for the club.
Edit to add this isn't even mentioning the incorrect naming of the opponents, such as "Hamilton FC" when it is Hamilton Academical FC or even Hamilton AFC which isn't great.