As a matter if fact one of the reason of actual success of IL2 1946 (it's still the most crowded sim online) is that you can play with hundreds of aircraft in tenths of scenarios.
If you're bored playing one, you take another, in a never ending experience.
This means longevity.
In a pay every addon model of business this can be done only by fiew people.
This means more players bored earlier and less people playing after a short time.
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