Photos taken at the Calgary event earlier this month show Smith wearing a head scarf while she stands smiling with members of the Sikh community.
Two comments were, "I like you, but this photo is inappropriate. You represent Alberta, not India. When did Wildrose change?", and "If you emulate the Muslim faith, I will NEVER vote for you."
Service Alberta Minister Manmeet Bhullar said in a news release Wednesday that such racism and bigotry has no place in Alberta, adding that if the Wildrose had changed, it would have not left them up for nearly a week.
Bhullar said he was at the parade with Smith and it was "extremely disappointing" that she hadn't commented on the postings.
Smith apologized, saying her party should have been more diligent in moderating their comment page over the long weekend, but as soon as they saw the postings, they removed them.
"I agree with Minister Bhullar, some of the comments were disgusting and out of line and bigoted and there is no place in our party for that kind of attitude.
"If people won't vote for me because I celebrate our cultural diversity, then good riddance.
"We're a party that embraces all people of all background and culture. The only way to confront bigotry is head-on, so I intend to continue going and celebrating our cultural events all over the province."
Bhullar said Smith "needs to issue an immediate apology for the reprehensible behaviour of her party's supporters."
Smith said she has no idea if the posters are Wildrose members or supporters, adding it's irrelevant because there's no place for their comments.
"We get hundreds and hundreds of comments on my Facebook page and we do have staff that regularly delete inappropriate comments. We missed a few this weekend, I apologize for that. It in no way reflects my views or the views of my MLAs or our party."
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