Baristas at four additional Michigan Starbucks stores voted to unionize on Thursday, joining a growing national labor movement at the coffee juggernaut and bringing the total number of union Starbucks stores in the state to nine. The latest Michigan stores to vote in favor of unionizing include 17410 Hall Rd., Clinton Township, 8-3; 2624 Lake Lansing Rd., Lansing, 13-3; 3343 Miller Rd., Flint, 13-6; and 1141 E. Grand River Ave., East Lansing, 19-0.