Remember, GO riders are paying $200+ per month, with some riders paying $250 to $300 per month. In addition, there's the TTC cost, add another $122/mth. So your looking at $400/mth. That is $4800/yr, never mind the capital cost paid for by your tax dollars for trains, buildings, parking, etc.
The capital and operating cost ride is $17.76 as of 2007. ( $905,585,000 capital and operating expenses divided by 50,986,200 rides)
There's approximately 98,050 actual people taking GO 5 days a week (50,986,200 rides per year, divide by 52 weeks, 5 days, and 2 riders per day --- just to be simple)
It's costing GO (capital and operating costs) roughly $9235/year/person, or $769.66/month/person, or $17.76/rider. And those taking GO probably own a car too, so add that on the true cost of taking GO Transit.
Any transit system should be a no brainer to take financially. To 50% of the riders, they can clearly afford it as there's about 50% of riders with household incomes of over $100,000/yr. What about those people who have a household income of $50/$60K a year? Are they not allowed to take GO and TTC because they need their car and adding on the extra $400/mth they simply can't afford?
Point here, is there's probably people that will ditch transit in favour of the car they already have and need, rather than the convenience (or inconvenience) of transit.