Do you know how Wicca started? Gardner and Valiente took parts of old beliefs, old traditions,old Gods and Goddesses, to form a new kind of "witchcraft" religion.
Wicca is of itself eclectic. But so are most religions. Added to, and subtracted from, over many years. Wicca is no different,really. If Gardner were alive today he would not recognise the religion he started.
Although there are those who stick to the original Wicca; there are many who do not!