[be] all fun and games

to be extremely pleasant or enjoyable

The idiom "all fun and games" is used to describe a situation that is enjoyable and entertaining. The origin of this idiom is not explicitly documented. However, the phrase is commonly used to convey the idea that an activity or situation is lighthearted and amusing. It is often used to emphasize that while something may seem enjoyable on the surface, there may be underlying challenges or difficulties involved.

Organizing a party may seem all fun and games, but it requires a lot of planning and coordination.
Being a professional athlete is not all fun and games; it involves rigorous training and intense competition.
While traveling can be all fun and games, it also requires careful budgeting and time management.
Working in the entertainment industry is not all fun and games; it demands dedication and resilience.
Playing a musical instrument is not all fun and games; it requires discipline and practice to excel.