Fair point, but I think it could be managed with the right model. It does not have to be a flat “replace the proven material damages” fine. There could be fixed (large) fines for any kind of significant misbehavior on top the the material damages, multiplication factors can be applied to material damages and adjusted until an effect kicks in, fines can be increased with repeat offenses, …

At some point clubs will just go bankrupt if they don’t take action against this.

Alternatively, instead of fines give them “yellow cards” or “red cards” depending on severity and ban them from the next game(s) accordingly, counted as an automatic loss in the league or tournament. Clubs will care about that a lot, same as most parents who might not care about paying a fine will care a lot about losing their daycare spot, if only for a short time.