Crystal doesn't allow the adding or removing of fields from the report. You can hide them, you can move them, and you can resize them, but you can't delete them.
If you are hiding something and you don't want the space left vacant, you can move other fields, or you can have alternative display sections and conditionally show or suppress them so that there isn't empty space, but these are all just tricks for making the display look nice.
So, yes, you give the impression that a field is not there, but you cannot actually remove it.