Carioca:

I suspect that Sao Paulo is part of the sale - it is listed for at least the Atlantic origins which would require a change in YYZ.

When the seat sales are advertised, often it clearly states that the fares shown are samples - other city pairs are on sale as well. While not so clear on this ad, it is likely the case as well.

The best bet, as always, is to call your travel agent and see what fares can be achieved.