$25 a month per head is usually not excessive. It also depends on what you consider entertainment.
Movie tickets? Yes. Cable or satellite? Goes in utilities.
I include the cost of a daily newspaper, an occasional coffee and fast food meal or pizza. No fine dining or gambling. Food eaten at work can be in its own category. Hope this perspective helps.
You should state what you actually spend on entertainment at the best approximation as possible. Thus, if you are a weekly movie-goer, have several magazine subscriptions and are enrolled in a sports club/gym, you may be more than average and should list your total. However, if you are not subscribed to such activities and do not go out that often, I agree that $25/mo is average per person. If you have a family, include what activities they are enrolled in and what subscriptions/memberships you have.