Sold well over 500,000 bells worth of turnips, yet still no Phineas?

I'll admit, I'm crazy when it comes to badges. The only bronze ones I don't have are the street pass and turnip one.

Since I live in a small city, it's probably impossible for me to get the street pass one, so I'm going for the turnip badge. My technique is that I buy a few thousand, use my other 3DS's town to get the bell boom ordinance and get a good price then I sell them at that town. I've gotten about 700,000 bells from it, yet I haven't seen Phineas. I've gotten other badges like a few silver and gold from him, but no turnip badge. Am I doing something wrong?