These stories will find place in Puranas only. Most of the Puranas contains skewed opinions/stories written to elevate the status of respective deities.
There was no idol worship in the Vedic Era. Gods were worshiped through fire only.
In the Vedic period there was no sectarian worship of GODS. Whether a person follower of Vedic of Life or not , That only mattered.
The reasons for change of worship in Sanaatana Dharma, otherwise known as Hinduism, are as follows:
- Till Mahabharata period, i.e, around 3102 B.C., the Gods from Vedic Pantheon were worshiped.
Lord Brahma is the Ruler of of all Worlds. - ब्रह्मा लोकाधिपो यथा (Srimad Ramayana, Bala Kanda). Indra's status was held next to him.
The Who is Who of Kings of Mahabharata Era, except a few, fought and got eliminated in the Mahabharata war. After the Rule of Pandavas that lasted for 36 years, no strong administration, directing the people in general in adhering to Vedic Way of life, in the entire country was in place.
This lead to decadence in Human values and grouping among various petty rulers.
Dominant rulers aided by some scholars created new Gods and started creating own groups.
(i) As a result, Vishnu, who was one among 33 Gods, had been elevated to the status of God of Gods.
(ii) Shiva could not found in Vedic Pantheon. The Vedic God Rudra's structure, appearance, status,etc, were altered and named Shiva, and was elevated to the staus of MAHAADEVA.
(iii) No mention can be found about Shakti or Rajarajeswari in Vedic Pantheon. Even Sri Krishna did not mention about her in his Bhagavad Gita.
(iv) The present day prominent God, Ganapati did not find place in Vedic Pantheon.
In order to elevate Vishnu, Shiva, Shakti , naturally the status of Lord Brahma has to be degraded, without which Vishnu, Shiva, Shakti cannot be marketed as God of Gods.
So all the Puranas were written inventing stories that show Lord Brahma in bad light and elevate Vishnu, Shiva, Shakti.