Low transmission rate links are bottlenecks that degrade the performance of Wireless Mesh Networks (WMN), especially when they co-exist with high-rate links. In this paper we investigate the incentives for mesh node sharing between different operators. Such cooperation aims to replace low-rate links with multiple higher rate links, and is induced solely from the improved performance that can be achieved through cooperation, even when the WMN operators act in their own self-interest. We present an analytical framework that can identify when the cooperation is expected to be beneficial for both operators, and estimates the expected performance gains in different scenarios, which include single/multi-channel and single/multi-radio cases. Analytical results indicate that there are cases where cooperation can yield significant performance improvements for both WMNs. The analytical results are validated with simulation experiments.