Why do some on here think of Ghandi as a sacred person?

Ghandi did travel some in his youth. He worked in South Africa for a while, experiencing their particular type of "Christian" culture. And in his homeland, he and his fellow natives got a good taste of (Christian) British imperial rule. (That's a big part of what the Indian Revolution was about.) So he did have a fair idea of what "Christians" were like in real life, and that idea didn't match what he heard Christians preach. As for claiming to be a member of all religions, I think he meant that sectarian distinctions were not important. For him it was the common humanity that mattered. He was not a religious leader. He just happened to make important political statements in a region where religious animosity was strong. One does not have to be a religious minister to make meaningful observations about religion.