that is the location of the program.
with trusted locations we are talking about the folder in which you put your databases. There will be a default location somewhere in the tools/options, but if you have a lot you are unlikely to keep them all in one folder, any more than you would keep any other documents in a single folder.
As I say, I am happy to set my own macro security to low, because I know what I will put on my machine - but I don't want to make that decision for someone else.