Service systems and their operation management are one of the most important and attractive scientific issues in, such as, management sciences and information sciences, and they are also hot topics in industrial and business areas. It is of great importance to design a reasonable profit allocation mechanism in a large-scale service system when cooperation of various cells is used to improve system's effectiveness and efficiency. To that end, we use the cooperative game theory to assign the profit allocation earned by the service units which are each of the $n$ independent parallel different M/M/1 queues. We design three allocation mechanisms by means of the ordinary Shapley value, the modified shapely value based on the coalition length, and the weighted Shapley value. Since the three mechanisms focus on the different aspects of profit allocation, we discuss impacts of the three mechanisms on the system's operations, and specifically, some numerical examples are given for analysis and interpretation in some practical issues.