In this segment, the author almost let the excerpts speak it all, concluding only on the last part. As part of his operation to prove the Church as a business, he showed how the Vatican had been gaining tons of money through tourism. There is cash also being added from souvenirs, church publications, posted stamps and coins.
There are three points to consider here, all real-life facts.
The author might hadn't noticed the word "economy" mentioned on the excerpts four times. Wikipedia's definition of economy is that it "consists of the realized economic system of a country or other area...". If it is written in the excerpt above that the Vatican's tourism plays a key role to its "economy", then it does not talk about personal business anymore. The Vatican City is a nation, an independent state. As independent, it does not mainly rely to any other state than what on its own can produce. As a state, it deserves tourism. As a state, it deserves profit, both from its own citizens or from tourists.
The Vatican also houses age-old masterpieces and artworks. The Vatican Museums contain masterpieces of painting, sculpture and other works of art collected by the popes through the centuries. These masterpieces deserves to be priced by many, for they identify history and human genius. A 18-euro visit to these old halls is worth it. Not everywhere can you find precious things preserved throughout the centuries.
The Vatican is the headquarters of the biggest and the oldest Christian Church in the world, and it is the most designated to represent the image of Christianity. No wonder why it had earned a lot in its tourism.
If it is not queer for the Iglesia ni Cristo® administration to open the gates of the New Era Central Complex in the near future, and to make it's edifices as landmarks and museums, then it will never be odd for the ages-old Vatican City to display its brilliance and vast time treasures.