What's the best way to control cloud sprawl?

Depends on whether you’re trying to control sprawl within your cloud deployments - if so, monitoring controlling use of your data through data security posture management tools is essential. Controlling sprawling use of SaaS should be a multidisciplinary approach from policy, financial oversight of spend and expenses and CASB

Consider implementing a Cloud access security brokers (CASB) tool which will  provide visibility, compliance, data security, and threat protection for any cloud-based service being used by the organization, expecially Shadow IT.