Towbars and insurance companies

Not for the first time I am changing my towcar , its always an exciting time with lots of things you have to remember to do. I have changed my insurance policy , updated my green flag and finally Ive booked a Towbar fitter. Whilst discussing the vehicle with my insurance company the lady tells me that fitting a towball is listed under modifications to the vehicle and as such they MUST be advised. That got me thinking as naughtily I dont think I ever have in the past, this hasnt stopped me from making a claim and certainly hasnt ever been mentioned in dealings with them before. I checked my old policy documents and its not mentioned on any of them. It isnt going to affect the renewal premium but Im guessing the fewer reasons you give companies not to deal with your claim the better. Anyone else NOT told their insurance company ?  Please dont let me be the only one.