Medium Transport; Low Wing; 2 Turbojet Eng
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 7
Communication Breakdown; Confusion; Distraction; Situational Awareness
ATC Issue All Types; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued New Clearance; Air Traffic Control Provided Assistance
Human Factors; Chart Or Publication; Procedure
Aircraft X departed ZZZ; and I re-routed them to 'FGHRN; then direct FAH; then as filed.'  The company filed ZZZ1..FAH.MADII1.KORD.  They flew the ERNNY2 arrival instead.  That is the way the company filed; the pilot never had to read back the arrival name.  They weren't required to.  When ZMP passed the flight plan to ZZZ tower; the controller would normally say; 'Cleared to ORD via ZZZ1; then as filed.'  So the pilot/aircraft/FMS flew the ERNNY2 STAR instead; which MKE approach was not expecting.There is no safety in this plan.  Two STARS; the MADII1 and the ERNNY2; are built right on top of each other; with similar fixes; so unless we ask the pilot every time; we have no way to know which arrival is programmed in the FMS.  Additionally; the pilot; when programming; could see the first fix (ZZZ1 or FGHRN) and push that button prematurely; without verifying the entire arrival.This situation is unsafe; and needs to be changed ASAP.  They need to have one STAR here; with different transition way-points instead of two STARS built on top of each other.
ZMP Controller reports of confusion of two STARS that go to one airport with similar fixes.  Controllers do not know what STAR the pilots are actually flying until reporting in or questioned.