It just occurs to me, why worry about them if all it can do is calculate sex and possible age the chances of showing an advert that might be relevant to that particular person is very small.
For example, the majority of Gransnetters are female and probably over 60 - and that is about all we have in common our incomes run from very tight to very comfortable, our attitude to clothes goes from track suit and t shirt to designer, our eating choices from limited by price, to no cook convenience to organic and cook from scratch. Some drink alcohol, others don't. Some love soap operas, some do not even own a TV and so on and so on.
So when on the very rare, less than yearly occasion I use a Tesco petrol station and their camera assesses my sex and age the chances of the advert they then show me being of any interest to me is very remote indeed.