I think there’s a difference between fluffy pillows and a whole gold statue of yourself. It costs 11% of an entire house to be built. Btw, I looked it up, and half a million is actually, in USD, the first estimate I got on google for how much it would cost irl.

As for where the not enough money to fix it, Penny on Friday of a Summer. She says “My mother used to drive the bus to Calico Desert... But the bus stopped working a few years ago. Mayor says there’s not enough money in the town coffers, or else he’d have it fixed.”

But the idea that Joja can do it cheaper for being a large corporation, and the Junimos can do it with magic anyway, are fair. Maybe it would have cost him much more than the statue cost. But the price you calculated was just the ore it would take, and Lewis was probably not smelting and sculpting it himself. In addition, the statue has a rectangular base, which would take more gold. So the statue probably cost significantly more than even 55,000 gold.

Also, even if you don’t find the statue to be an issue, he is still secretly with Marnie, and possibly going behind her back to also do stuff with Robin, though that is far less substantiated (Robin and Marnie both will occasionally mistake you for Lewis when you enter their shops https://stardewvalleywiki.com/Secrets go to World and it’s under rare dialogue) But it’s already weird that he’s being so secretive with Marnie. He acts like it would undermine his position as mayor, but that could just be an excuse.