Currently PDF export in Creo Parametric saves all shaded graphics in raster.
For DRAWINGs, to get "shaded" PDFs with VECTOR graphics, you need to set to non-shaded view displays (ie: NO HIDDEN) and manually fill (Layout>>Hatch/Fill) and color individual feature surfaces one by one. This is tedious and time consuming.
There should be an export OPTION to directly convert shaded views (in ALL modes; ie: ASSEMBLY, PART and DRAWING) into VECTOR graphics with shaded/rendered areas as distinct FILLED OBJECTS in the assigned part colors with lighting gradients.
Furthermore, this vectorizing option should be given to all vector capable export formats (eg: *.DWG) and more vector graphics export formats should also be added (eg: *.ai from Adobe Illustrator).
Creo Parametric 2.0 is able to export text as TEXT, if you configure it to use TrueType fonts in drawings.
My bad. You are right. I have updated my submission accordingly. Thanks.
Amended my post again. This time, I added the work around I managed to come up with to get vector "shaded" objects.