Every business is different. In the software business having 1000 customers for 1$ is not preferable over having 100 for 10$ due to the hardware footprint and support personnel. You also have to take into account the following: Does HT want 20 more customers for 5$ that leave after a few months or 1 for 15$ that stays with them for 10 years?
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You are correct that there are many factors to be considered. Many trade-offs to be balanced.
For instance to the question: is having 1000 customers for 1$ vs. 100 for 10$...
Overhead costs as you suggested are one factor.
Another might be variation sensitivity. A 10 player fluctuation in one would be a 1% drop in revenue, in the other a 10% drop. The fewer, higher paying customers, the less diversification. THe more sensitivity to small changes. I've seen small companies make a mistake of allowing too large a percentage of their revenue from too few big customers.
Another factor is critical mass. The fewer the customers, the greater the chance of dropping below critical mass. Then you enter a colony collapse cycle. Players start leaving because there aren't enough players to make it fun...which leave fewer players still.... recurse.
In regards to overhead alone, the idea scenario is 1 user paying $1000. But they will soon leave due to lack of critical mass, and then your income would go from 100% to 0% instantly because of variation sensitivity.

Regards,
Wab