It's also useful if we have to parallel another aircraft with yours and we don't need you to turn...or we just ask you for your hdg, but it does help if we are busy if you report it.
On a similar note, are there differences in SOPs between how you report hdg? I have been training on Clacton for about 6 months now and can't see any pattern i.e exact heading or to closest 5 degrees.