The financial benefits of energy sharing within a community is impacted by factors within the control of the community, such as internal rules for energy sharing, and by external factors, such as regulatory frameworks and fiscal policies. While much of the literature on energy sharing has focused on internal rules, there has been less attention paid to the role of external factors, despite their potential policy implications. This study aims to address this gap by examining the range of fiscal measures that can be used to regulate energy sharing in renewable energy communities in 39 countries. The study considers two community arrangements: one in which prosumers share their surplus energy, and another in which consumers shares the energy generated by a collectively-owned PV. The findings suggest that the annual savings from energy sharing in the first arrangement may not be significant enough to justify the formation of the community. In contrast, the cost savings from sharing energy in the second arrangement are much greater, but also more influenced by the fiscal support policies. Based on the results, the study offers policy recommendations for avoiding resistance from stakeholders and aligning their incentives when introducing energy sharing regulation.