Sorry, but a birthday party isn't a birthday party without a cake and - a birthday cake isn't a birthday cake without at least 1 candle to blow out!!!!!!!!!!!!!
Once I've photographed the cake, I don't really care what they do with it!!!!
I don't supply them unless it's something like a Barbie cake, where they candles go on the board rather than in the cake itself.
I only do cakes as a hobby and do not sell but always ask the person if they need the candles. Most already have their own candles. When I made a cake for (neighbor) a child who was Latin American, I went over and the birthday girl put her face right into the side of the cake. They said it was a tradition of the children to do that. If I had to vote blowing out candles verses smashing their faces into the cake I think I would vote for blowing out candles instead. They always take pictures of the child once she has the cake all over her face.