There may be some misunderstanding and unnecessary fear at the mention of "armed guards". What I see are off duty cops who act as greeters but have their service weapons with them, "Just in case".
I know Tom G2 is widely traveled, and'll get a kick out of this:
...I don't think that most Americans and Canadians really know what real "armed guards" at shopping, bank and retails outlets means...
If you want to see seriously armed retail store and bank guards, visit Guatemala, Honduras, etc...where the "armed guards" outside many banks (and inside MacDonald's restaurants, among others) are regular Army (dressed in full battle fatigues, with Uzis and other automatic genres), and private security, carrying combat shotguns...the regular Army guards (with Uzi automatics) at the Guatemala banks I used to frequent also acted as "greeters"...
THAT is what I call "armed guards"... :B
On the other hand, it could be that every adult male and female in Texas (and, Florida) are carrying concealed sidearms; so on any given day, any Walmart in Texas or Florida will have 2000+ armed shoppers, too :p