Maybe that's a post facto rationalized reason, as I'm sure it did draw in more tributes, but that's like saying folk tales across the world's sole purpose is to have sacrifices when in reality people just like making up and telling stories. It's like saying the apostles of Christ only spread his message to raise money for the Catholic Church, no doubt that was a side effect but it wasn't the "point" by any means, especially early on where there was no church.
> Maybe that's a post facto rationalized reason
Isn't this what you're doing with the idea that the Sri Racha story is obviously meant to sell?
One is plausible as the primary reason, with documented instances of it happening, as I had linked before, while the other is mere conjecture.