There are analogies for keeping similar illusion alive, like:

https://en.wikipedia.org/wiki/Professional_wrestling

"The matches have predetermined outcomes[11] to heighten entertainment value[12] and all combative maneuvers are executed with the full cooperation of those involved...These facts were once kept highly secret but are now a widely accepted open secret. To promote and sustain the willing suspension of disbelief by maintaining an aura of verisimilitude, the performing company avoids discussing the true nature of the performance in official media"

And these are adults.

These girls may continue their hobbies in adulthood too (like most people keep playing the games they like at older age...)