On the other hand, those seats you don't build yet are earning you nothing this week, or next week, etc. The important thing is to try to make sure you can find as much money as possible to invest in the arena while still being competitive, and that's usually easier when you first start out. :)
The big difference is that you still have the money for the empty seats you
didn't build, and you have the option to put it to work for you, an option lost once it is sunk into empty seats.
Yes, I agree that investing in the arena while still being competitive is the key balance, which is a far cry from an unqualified "build as big and as fast as possible."