Road signs in UT

A little over HALF of states it is illegal to drive with 'hazard lights ON'

Rules in Your State
Driving with Active Hazards Lights Prohibited

Alaska
Arizona (except in an emergency)
California (except to indicate a traffic hazard)
Colorado (except if the vehicle speed is 25 mph or less)
Delaware (except to indicate a traffic hazard)
Florida
Hawaii
Idaho (except to indicate a traffic hazard)
Illinois
Indiana (except in an emergency)
Iowa (except to indicate a traffic hazard)
Kansas
Louisiana
Maine (except to indicate a traffic hazard)
Maryland (except in an emergency)
Massachusetts
Minnesota (except to indicate a traffic hazard)
Montana (except to indicate a traffic hazard)
Nevada
New Mexico
Ohio (except when a hazardous condition is present)
Oklahoma (except in emergency situations and to indicate a traffic hazard)
Rhode Island
South Carolina (except to indicate a traffic hazard)
Tennessee (except in emergency situations)
Virginia (except to indicate a traffic hazard or when traveling slower than 30 mph)
Washington (except to indicate a traffic hazard)
West Virginia (except in emergency situations)
Wisconsin (except to indicate a traffic hazard or when a hazardous condition is present)

Driving with Active Hazards Lights Allowed,

Alabama (unless otherwise posted)
Connecticut (unless otherwise posted)
District of Columbia
Georgia
Kentucky
Michigan
Mississippi
Missouri
Nebraska
New Hampshire
New Jersey
New York (unless otherwise posted)
North Carolina (unless otherwise posted)
North Dakota (unless otherwise posted)
Oregon (unless otherwise posted)
Pennsylvania
South Dakota
Texas
Utah
Vermont
Wyoming


So maybe that sign is necessary after all