If their model really is so much more efficient, they should be able to run it cheaply even on rented infrastructure. If somehow they got so many users that they can't even rent the infrastructure quickly enough and they have to make people wait in a queue, that would be even better advertising.
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Could also be they don't have enough funding to sustain that many users, or even the infrastructure lined up.
If their model really is so much more efficient, they should be able to run it cheaply even on rented infrastructure. If somehow they got so many users that they can't even rent the infrastructure quickly enough and they have to make people wait in a queue, that would be even better advertising.