The By-Law that you have referenced is the standard By-Law #2 provided in Schedule 1 of the NSW Strata Schemes Management Act (1996), and which most if not all Strata Plans have adopted to prevent people like you from regularly using visitors’ car spaces illegally.
If your Plan’s Strata Manager receives sufficient complaints from Executive Committee Members or indeed from any Owners about a person regularly (like every Thursday) using visitors’ car spaces illegally, then they’re entirely within their rights to issue that person with an advisory letter, and depending upon their delegations under their Agency Agreement with the Owners Corporation (O/C) that letter could be followed by a formal Notice to Comply, where monetary penalties can be applied.
You regularly parked in the visitors’ carspace, right? So how is a general advisory letter about that bullying? Rather, it’s merely an O/C complying with its legal obligations to enforce compliance with its By-Laws. If Owners don’t want a parking By-Law enforced, then they can vote to repeal that By-Law at a General Meeting, and parking anarchy will likely result in you and other Owners not being to access the garages at all!
So unless you’ve got deep pockets, I’d strongly advise you to either seek the written consent of your O/C to park your vehicle in a visitors’ car space during specific times on specific day/s, or park your vehicle on the roadway whenever you need to access the items stored in your garage.
Not the answer you wanted I’m sure, but that’s how it is!