Should clubs be penalised for the behaviour of their fans?
Unarguably, the club must be responsible for taking action against improper conduct of the fans but the behavior of the fans is not under the control of the club. Fans aren't chosen by the club so their actions so the club cannot be held answerable for their behavior.
How is it fair to a sport team that the actions of the fans become a direct consequence of the team? For example, is the suggestion here to fine an MLB team $50,000 if some crazed drunken fan decides he wants to run on the field and literally "steal" second base? This is in no way solving the problem. The owners of the ballparks and security teams own this responsibility for keeping the environments safe, and as long as the ballclub is not CAUSING or PROMPTING poor fan behavior (in ways other than sport performance, of course), then the club should not be penalized.
Look at hockey and Vancouver. The Canucks admitted on television that they were embarrassed with the riot their fans had in the 2011 playoffs and thought that they would of acted more maturely.
If a guy murders someone with a knife..should the company that made that knife be penalized? Of course not.