The gods play games with the fate of men. Not complex ones obviously, because gods lack patience. Cheating is part of the rules. And gods play hard. To lose all believers is, for a god, the end. But a believer who survives the game gains honour and extra belief. Who wins with the most believers, lives.
Believers can include other gods, of course. Gods believe in belief.
There were always many games going on in Dunmanifestin, the abode of die gods on Cori Celesti. It looked, from outside, like a crowded city.* Not all gods lived there, many of them being bound to a particular country or in the case of the smaller ones, even one tree. But it was a Good Address. It was where you hung your metaphysical equivalent of the shiny brass plate, like those small discreet buildings in the smarter areas of major cities which nevertheless appear to house one hundred and fifty lawyers and accountants, presumably on some sort of shelving.
The city's domestic appearance was because, while people are influenced by gods, so gods are influenced by people.
Most gods were people-shaped: people don't have much imagination, on the whole. Even Offler the Crocodile God was only crocodile-headed. Ask people to imagine an annual god and they will, basically, come up with the idea of someone in a really bad mask. Men have been much better at inventing demons, which is why there are so many.
*Few religions are definite about the size of Heaven, but on the planet Earth the Book of Revelation (ch. XXI, v.l6) gives it as a cube 12,000 furlongs on a side. This is somewhat less than 500,000,000.000,000,000,000 cubic feet. Even allowing that the Heavenly Host and other essential services take up at least two thirds of this spate, this leaves about one million cubic feet of space for each human occupant-assuming that every creature that could be called 'human' is allowed in, and that the human race eventually totals a thousand times the number of humans alive up until now. This is such a generous amount of space that it suggests that room has also been provided for some alien races or - a happy thought - that pets are allowed.