Obviously, tax laws in every country are used to support local industries/interests. Nothing new there.

AFAIK, you can deduct the cost up to the posted limit by Revenue Canada. You are also required to log ALL TRIPS made for business with starting and ending mileage, reason for trip etc. You can't claim personal trips as a business expense and therefore these should be excluded. Not sure if they have relaxed the limits now.

Regarding the S class I remember a case where a company bought an S class for its CEO to use and they also had to pay 40% tax on the purchase price (it was 170k) the CEO owed to Revenue Canada as that was a taxable benefit (same as in the UK).