The answer is that there's no ideal corporate sponsor that could possibly inject enough money and infrastructure to a professional US tour to ever make it worth their time or money. Period.
Pool in the US will never get past the image of gambling in a smoke filled bar (even though bars are now non-smoking). Pool has no developmental system. Yeah there are pockets of junior leagues around the US, but nothing like organized club sports. These things make it hard to market to the masses, which in turn make it hard to get any return on investment for the sponsor.
No to bad, but the real question is who's the sponsor?