Around here Lowes & Home Depot did not have the 20V Max hammer drills when I checked a while ago. Only the non-hammer versions. I bought mine on-line, the difference in price was minimal and I needed hammer action anyway.
Yes most people go for Hammer Drill because it has the ability to switch the hammer action off and on as required.It has other benefits as well.It can penetrate any hard surface within few seconds provided it has enough power backup.