Yes we are! Summerslam we booed Eugene and Cheered Triple H. Also cheered for Orton to win the World Title vs Benoit.
I recall the booing of Eugene (and the cheering of Edge in his IC title match), and I recall some cheers for Orton, but I do not recall people blasting boos at Benoit or wanting him to lose. Orton was in the midst of his first face turn since joining Evolution, but I would hardly say that everyone wanted Benoit to lose.
I do recall, however, the crowd in Hamilton booing the ever-loving shit out of Ken Shamrock and cheering wildly for The Rock at Breakdown in September, 1998. Shamrock turned heel not too long after that, and The Rock did his short face turn before becoming the Corporate champion. (Remember, Rock was a big time heel at SummerSlam '98, facing Triple H in a ladder match for the IC title).
Canadian crowds do tend to be a little bit nutty. That said, Austin was always popular from what I can recall, so I doubt the Mania crowd would have booed him like they did The Rock. The Rock's act was growing a bit stale at that point, so people were starting to get sick of it. I guess it was just lucky that Canadian crowds can be a little ahead of the curve when it comes to who to cheer and boo. Hogan still would have gotten the gigantic pop he did, but I doubt Austin would have been booed out of the building like The Rock was.
P.S. I was at that Mania, and I have never heard a crowd so loud in my life. The concrete floor beneath me was shaking because the place was so loud. Anyone who was there will attest to how awesome a moment that was. One of the top 5 in WWE history, if you ask me.