Apparently this is a big thing among some circles. Like Mushroom Mountaineer vs Bamboo Shoot Villager huge.

Reminds me of Kronk's kitchen scene:
"4 combos extra bacon on the side, 2 chilly cheese samples, a basket of liver and onion rings, the catch of the day and stake cut in the shape of a trout. You got all that, honey?"
"Three oinkers wearing pants, plate of hot air, basket of Grandma's breakfast, and change the bull to a gill, GOT IT!"

Recently Sukiya started an ad with a sales copy like "Please call it Tondon". As far as I know from living in Japan, "butadon" is the common reading and "tondon" seems to be a unique reading of Sukiya.

On the other hand, the reading of 豚汁 seems to be a regional matter. According to one survey, "butajiru" is a common reading in western Japan and Hokkaido, while many people in eastern Japan read it as "tonjiru".