From the OS'es point of view, SQL Server is a service; only local admin privs are enough to restart a service.

I had a similar problem with another product, and I was strictly required not to give local admin rights for junior admins. The workaround I had to use was far from elegant, but quick, simple, and kept me from granting excessive privs - configure a share, grant modify rights to the jr.admins for that share, schedule a batch under priveleged account which checks whether there a file in the share; and if so, restart the service and clear the share; then instruct jr.admin to put the file in the share should a problem arise.