It appears the process goes something like this. A real estate developer finds an area they think would be a good location for a big retail store like Wal-mart. They look at buying up the properties, they put together a business plan, and they start selling the idea to Wal-mart and to the city.
They negotiate property tax breaks with the city to help attract Wal-mart to their area since they will bring in large sums of money in the form of sales taxes and income taxes from the company and it's employees.
However, they end up with some people who don't want to sell, or who are leasing some of the property and won't allow their lease to be bought out so the property owner can't sell the property so that it can be used for the store.
Therefore the developer works with the city to make those people leave or sell.
While Wal-mart may not be directly involved in this process they are at least passively approving it. Even when they've been notified by others they have not declined to build a store in such an area if the developer attains the property through eminent domain. If Walmart were to refuse to build the store if the property were attained in that way, the city would have no reason to use eminent domain, unless another retailer is also interested in building there.
The city, the developer, and Wal-mart all deserve a share in the blame.
It may be true that if Walmart refuses to build there another retailer may do so instead. That may mitigate Walmart's blame to some extent in some people's opinions.
You should have started your comment with this statement. It would have saved you some keystrokes. As a business, Wal-Mart will and should work within the laws that exist. Wal-Mart is not to blame at all for eminent domain actions. If they went out of business, eminent domain would still occur. And I personally would much rather see a pay-to-play Wal-Mart than some community center that requires public tax dollars to operate.