Hope we get other comments.
I hope you do too, this is an interesting question you raised.
I was thinking that as the requirement is for GFP we had an option of using GFP or GFCI.
Now I am not as sure, for ice melting equipment.
We are required to provide OCP that is adequate for the load so why wouldn't we be required to provide ground fault protection that is adequate for the load?
I know we use some type of GF for protection for all of this equipment and many times it is GFCI type for small sections of heat trace, it seems to work fine.
The larger jobs we use GFP breakers.