Caste discrimination without knowing

31M here. My Mom used to tell me that you shouldn't enter home if you got hair cut even though you washed your hair in saloon. I thought it was a higene practice. Last Sunday she told me to enter. I asked why now? She told me that if Ambattar touched you. You can't enter without bathing yourself even it's your own home. I felt so stupid after realising this. Coz after opposing the caste discrimination in work place/neighbourhood I realised that it's still in our home. Anyway she told that we're now as one so no need to be follow these anymore. Please let me know what else we follow as caste discrimination in the name of culture.