I don't think so -- there are a TON of players who are longtime showboats. MJ used to do it -- Timmy Hardaway used to do it -- but they told their opponent what they were going to do -- they didn't tell the opposing bench!
But my biggest reason for feeling that this was more than showboating is that VC's heart hasn't been in Toronto all year long -- and it's been pretty obvious, IMO, in his game. Add that together with what he did and I don't think it adds up to showboating!