Why don't C of E graves have photographs of loved ones?

Apart from Church Yard burials, which are now extremely rare, the Church of England does not operate exclusive cemeteries. There is, however, absolutely no religious/denominational reason why Anglican graves can not have photographs on them and many in fact do. However, there is an increasing number of restrictions imposed by individual cemeteries including no photographs, no statues and no grave surrounds. Some of these restrictions are related to space saving, ease of maintenance, keeping up the appearance of the cemetery over time and now also, so I'm told, so as not to cause offence to other religions/atheists. I would guess that photographs might be refused on the grounds that they may fade with time making the grave "untidy". I might add that the authorities in Britain now also put considerable effort into persuading the bereaved to have their loved ones cremated rather than buried.