I don't walk down the center of the parking lot lane, but I do keep my distance from the parked cars in case one starts backing out and to give myself more room if someone pops out unexpectedly from between the cars.
How in the hell do you get out of a grocery store with only two bags of goodies?!?Why should I use a cart to take two bags to my car? I can open my fingers and let the bags drop as I move my hands to the gun or knife.
Even so, I use the shopping cart because it's faster for me to let go of a shopping cart than to toss the bags I'm carrying. Yes, toss. I'm a technician by trade and typically, anything I drop (tools, heavy/sharp objects, cords, hoses), will injure my feet and/or tangle me up. When I drop something, I have to get out of it's way or get it out of mine.
As for the cell phone, mine is hands free, thanks to the fancy hearing aids I got from the VA.