The price of McDonald's 10 wing bucket is 66 yuan, which is the pricing strategy decided by the restaurant. The formulation of pricing strategy usually considers many factors, including cost, market demand, competitor pricing, etc.

Specific to the pricing of McDonald's 10 wing barrel, there are the following possible explanations:

1. cost factor: cost is an important consideration for enterprise pricing. McDonald's 10 wing bucket contains 10 chicken wings and some extra side dishes. The price setting is likely to be based on the cost of raw materials, cooking, packaging and so on.

2. Market demand and competitors: Pricing will also be affected by market demand and competitors. If the market demand for this product is high, and the competitors' pricing is in the same price range, then McDonald's can price it at a higher price to get more profits.

It should be noted that this is only based on general pricing analysis, and the specific reasons may involve more business considerations and market strategies.