Banks are not my clients generally, but if I were called upon to advise a bank on whether or not to give a loan, I'd be looking at that provision and saying your ultimate debtor here 18 months hence will be an unincorporated association, and unless you have adequate guarantees that are personal to individuals, you can't sue that unincorporated association—meaning an electoral district association—to recover the debt.
There are mechanisms that will vary from province to province for bringing something in the nature of a representative action, where instead of suing that riding association, you bring the action against individual officers of the association, but what you are getting at is the association's financial resources, as opposed to their own financial liabilities.
The concern you identify, I think accurately, is whether this might have a bit of an effect of imposing some financial fear upon party volunteers from all sides as to whether they're going to be put, at minimum, to the expense of defending themselves, and whether individuals, for various reasons, are going to weigh one more factor against engaging in the political process in support of parties from all sides of the House.