I've only just seen this.
What actually happened was, as I exited the store into covered bit just outside the doors you get at most supermarkets, he was directly in front of me, walking very slowly and not particularly straight. I went to walk to his right when he made a sudden turn to the right which put his trolley right in front of me, and I couldn't avoid it. Accidents happened, but I noticed straight away he wasn't looking where he was going, and when I bashed into his trolley he briefly looked up from his phone, looked at me, and the looked down at his phone and walked off across the car park.
I'll take mid to late twenties btw Thanks.