A few points here. Firstly, I would not go into battle based on anything anyone from Fair Trading told me over the phone. They can only reliably tell what you can and can't do based on the by-laws of your building, not the 'model' by-laws on their screens. The fact that many of their operatives don't even realise this themselves is enough reason to take their advice with a massive pinch of salt.
Which brings me to point 2 – what does it say in your by-laws? If there are items like keeping the appearance of the car park tidy etc etc, or not storing goods in car spaces, then your EC has a case. Whatever it says, the Notice to Comply has to state which by-law is being breached. If no by-law is being breached then they have no case. Again – this is YOUR by-laws: not the model by-laws or the ones you think you might have. It's the by-laws held by your strata manager and secretary and of which you should have an up-to-date copy.
Point 3 – just because 'everybody else is doing it' is not a reason to breach by-laws. If you and the majority of people in your building think there should be unfettered use of parking spaces for storing goods but your by-laws don't allow that then the time to make that point is at an AGM (or EGM held to discuss the issue) where you can vote to change the by-laws.
Notions of what is acceptable or otherwise regarding the neatness of stored goods is purely subjective and therefor meaningless unless it is specified in a by-law.
The question of the chairman's car is a different issue entirely as it sounds like he is (partially, at least) parking on common property, by any objective measure, and that is likely to be forbidden in the by-laws.
If the fire safety authorities are genuinely concerned then they will issue a fire order to which you and all owners must comply.
Also, being 'breached' for one issue isn't invalidated because you have a complaint, however valid, about another issue. If there's a level of hypocrisy at play in your EC, then the time to raise that is at an AGM when the EC is up for election.
There is a solution to all this. Early in the history of my building they passed a by-law requiring goods to be stored on specially designed boxes that sit off the ground so you can park the nose of your car under them (the company is called Box Thing but there are other brands). It's a compromise solution that gives everyone a lot more storage, keeps the garage neat, avoid fire and vermin problems and isn't too expensive.
I would suggest your OC approves a couple of options and sets a date, say six months hence, by which time everyone either installs one or clears their stuff from their car spaces – problem solved.