Well, I don't think so, but I know people who do. One of the gripes I hear more often as not is Walmart doesn't support their employee's right to medical benefits, i.e.: their right to be represented by unions in order to force the corporation into paying for a portion of the employee's medical benefits.
Of course this argument doesn't hold much water. There is no requirement in this country for an employer to provide medical benefits for their employees. The problem is since most large businesses do provide these wonderful benefits it becomes a requirement defacto in the minds of the "entitlement mentality".
HOWEVER!!! These people fail to understand the basic nature of human beings... If you subscribe to the entitlement mentality you do nothing to improve your lot in life because someone should do that for you. If everyone lived by this philosophy humanity would not have progressed to the level we have. I know... The people who live in this sort of world (described above) would argue humans have advanced to a destructive point in this planet's evolutionary chain, and we should eliminate our progress and regress to the point where we will never reach our own peak.
The latest gripe I've heard though, is about Walmart's business practices unrelated to employee relations. More specifically, to the practice of purchasing mass quantities of merchandise and goods from third world country based companies willing to provide for the prices Walmart is willing to pay. Their argument against this is that Walmart is forcing these companies to pay extremely low wages in order to provide the products Walmart demands at the prices they are willing to pay (wholesale) so their profits enable them to stay in business.
While I agree these businesses should pay their employee's more, I don't think Walmart is the culprit. Their practices are based on current governmental laws regulating business practices in every country they purchase from, not just the US. Thus, if a country refuses to set laws regulating company/employee relations the companies in that country will work their hardest to garner the interest and business of companies like Walmart because there is no incentive (like the lack of a prison term) to deter poor employee relation practices.
Instead of blaming Walmart for the relative poverty of the working class in other countries maybe liberals should blame the governments of these countries... But that's just what I think.