What is to fear?

The KNS and the governor have come out against specialty plates being offered to Tennesseans. They had no problem with the system until a pro life plate was allowed by the state a few years ago. The plates have to meet a simple standard of offering and passage by the legislature, 1000 pre sales of the plate as well as the money going to a nonprofit cause. To my knowledge even the liberal Tennessee court have said none have ever been proven to be a problem. What is the fear that could happen? What is it that has them so turned up about this issue? Is the thought of this that has them in a bind?