Paranoid owner

So I was at Eastgate to meet a friend a friend for lunch, so I thought since worked at Mega Mica before, let me go and say hi to some of my ex colleagues.

Met everyone and said my hellos. Went to lunch and came back to the shop. As I was waiting for my friend to finish for the day, I was waiting by their old coffee shop at the edge of the counter. There happened to be a computer there, which I didn't touch at all.

The owner walked by and saw me there, he called the sales consultant who was there with me and questioned him about what he was doing with me. I remained where I was standing and one of the security guards came by to ask how I was doing following the passing of my brother who was also employed at Mica Eastgate as a driver. While I was explaining to him, this owner comes back to us and asks if anything was broken, looking at his computer. I looked at him puzzled, thinking he was just being funny.

I picked up that he thought I was doing something in his shop that I shouldn't be doing so I moved from the counter, to the electrical department to purchase a plug.

Next thing I hear that security is asked to watch me and that a manager was requested to ask me to leave.

I get that he is paranoid (as I've always known him to be), but I'm just irritated because he could have simply asked me directly what I was doing there, instead of acting like I ****** the shop of millions or something. I don't appreciate whatever he was insinuating with his behaviour, and honestly if that is how they treat customers or specifically ex employees then ja, I'm happy not to return to their little store.

FYI: I can actually afford to pay for anything I want to buy, and he sells nothing I'd even want to ***** so he must just chill, the place isn't even all thaaaat in a bag of chips.