if you think only religion makes you bad, then what about the leftist/communist/marxist? the bigots,anarchist and slaughters were ever they ruled? 

if you think untouchability was only with hindu religion, then you have not seen a rich person’s home in which the poor have everything different? not seen a servant’s wash room? guard room etc? the poor people were not even allowed to sit in their sofa, chair or bed. what made these poor became untouchable so that even have separate glasses and plates to eat food in such homes? 

Go and visit film sets, there you can see the rich- poor, fame- fameless technician divide in its full glory, separate foods are served in sets based on all these. the actors behavior to the light boys or lesser technicians is crude form of untouchability. 

Go to europe or any western country they practice racism irrespective of religion, is not that another form of untouchability? the way (NO1 educated) keralites see bengali, up, biharis is nothing but racism, same is the case of north indian people viewing south indians, 

 if you go to any priest or politician you have to keep your heads low before their whims and fancies.

good or bad is a person’s second nature, religion, politics, money, race are only channels to superimpose their wickedness. untouchability comes when one start to feel superior complex in their mind. as long as that ego is there the untouchability and badness remains in some form or another.