If the HOA is a corporation with the residents as shareholders, then Walmart or whoever can go to the council and offer to buy out the area or make an exception. The local neighborhood can vote on whether to allow it to go through, or ask Walmart for money to compensate them for the disruption. There's very little friction if Walmart is willing to come to an agreement with the neighborhood. The worst case is that Walmart buys the HOA corporation, and there's always some amount of money that will buy people off.
If the local city manages it, then it's a long drawn-out process of lobbying for zoning controls that apply city-wide. And offering the citizens money to vote for it might be illegal in some jurisdictions. Even if Walmart and the local citizens are okay with it, a couple hold-outs or people from other neighborhoods can delay the entire process by complaining to the zoning board.
If the local city manages it, then it's a long drawn-out process of lobbying for zoning controls that apply city-wide. And offering the citizens money to vote for it might be illegal in some jurisdictions. Even if Walmart and the local citizens are okay with it, a couple hold-outs or people from other neighborhoods can delay the entire process by complaining to the zoning board.