Is proselyting inside Walmart against their policy?

It’s 4th of July. Sister missionaries are walking around Walmart proselyting to the workers and customers and not buying anything. I don’t care if they are doing it in public spaces that our family doesn’t need to be, but Walmart has our groceries and necessities. Are they allowed to do that or is it against their policy? The HR worker there said if they aren’t selling anything then it isn’t solicitation and it is protected by free speech. She said if they do anything they could be charged with harassment. The HR worker was young though, and I’m not sure she has ever had someone ask about this. I also called corporate but they weren’t helpful (or I wasn’t communicating well enough) and kept forwarding me to someone else.

I support free speech, but I don’t want to be preached to when getting groceries if there is already a policy that prohibits it. I don’t want to be tempted to walk up to the black guy they were trying to teach and tell him what Mormon’s really think about black skin. I might be on the losing side here, and that’s ok if that is the case. I get that we all need to learn how to tolerate each other in society, and I still have some personal healing to do. I thought I would ask anyways so I can learn to stand up for my own interests in life - something the church never allowed.

Does anyone know if this is against Walmart policy, and … am I the asshole here? I’ll own up and do better if I am lol.