Everyone here is forgetting to account for how much it would cost to demolish the SkyDome. When it was built, there was talk about how much reinforced concrete and steel were in the structure, that it would be there forever. It would need to be demolished with explosives. When it was in the middle of nowhere, that seamed feasible but when talk about a new stadium started to percolate, a review of the structure and its new proximity to a community of glass towers made the explosive detonation impossible and taking it down piece by piece would cost hundreds of millions, just to clear the space for a new stadium, let alone the cost of the stadium. Hence why they opted to update the existing stadium. The SkyDome isn't going anywhere in our lifetimes. The Jays may move, but the stadium will outlive us.