Charging a $2 Capital Fee for ticketed Museum events

Hello, We are considering adding a $2 (+HST) capital fee to all ticketed events at our museum, The Bruce County Museum & Cultural Centre. This fee would not apply to general admissions or memberships, just to events (for example, our scotch tasting or lecture series) where the purchase of a ticket is necessary. Do other facilities charge a similar fee, and if so, what has been your experience? Thank you, Maria Canton, Development Office