I think you're changing the hypothetical a bit. The question was if he actually had existed, not whether the NT account represents an accurate portrayal of such.You have a good point, but even so, if there was a magical person out there who was the real deal that might have more repercussions than that. There's a verse where it says he had to send away the hungry or preach from a boat, well the fact is in reality that would quickly turn into non-relenting and constant situation. The people who said 'oh another one' would literally be dragged out to wherever this magician was, I think. The roman empire would recognize it a lot quicker as well, wouldn't they?
But still, I think those in the surrounding neighborhoods would have been more likely to have been the ones on line. Think about how long it took to travel back then. To up and go on a journey of months (at least) just to follow up on a rumor of another healer. Let alone how long after the fact, they would have actually heard that rumor. The masses didn't have that much time or money to waste.