Meh- the NHS is a good thing.  But people are people all over the world, difficult, doubting, obstreperous.  The "test" is a reaction to people bigging up their illness.
In my mind, the same applies as a migraine test.  People clutch their heads and moan about having a migraine 
while sitting at their desk and working!  Or my ex-landlord having one all day... but listening to the radio and making himself 
real coffee and 
real porridge (from oatmeal)...  
No.  
If you have a migraine you hope you have a brain tumour, because at least that means you'll be on opiates until you die.
And if you have influenza you don't behave like someone who fancies a few days off work.  Maybe Brits don't make the best Doctors though