Images Stolen by Print Shops?

[Go4EVA!]

I've read numerous threads about people having their photos stolen through various means of downloading from the internet, but my question deals with the risk having photos stolen by print shop stores/companies?

Back in the days of film, I took one of my negatives in to a local photo processing shop for some custom work. I got my enlargements, and I was happy. A couple weeks later, I went into the same store, and noticed that the owner had one of my photos printed, framed, and hanging on the wall. I confronted him about it, he recognized me immediately, and simply said that he "collected" nice photos from his customers to decorate the shop....

So, now I'm decorating a new home & office, and I'd like to print up some nice enlargements, and I'm wondering about how to protect my digital media. Is it even possible? I'm not a pro, just a hobbyist, but I still prefer to handle my photos carefully. Any recommendations on good/trustworthy places to print enlargements? Thanks.

[5x5 photography]

When I get my images printed I bring them in on a flash drive, have them printed, and take the flash drive along with my prints home.
I do not leave anything behind with the original digital data.
Maybe they can store that data after the image is printed but I believe that it is unlikely they will, especially if it is a reputable store.