Volumetric (Vehicle range) reasons. Compressed natural gas is still 1000 times the volume of it’s liquid counterpart.
Of course it depends on how much compression, but it is going to be more like 2~5 times, not 1,000 for typical transportation-type storage tanks.
And everyone thought that these unit crude oil trains were rolling bombs?
These fuel tenders of LNG will be right next to the power... no “cover cars” as all railroads require for other Hazmat.
I invite everyone to search the web for the term “BLEVE”.