Treated as an UE driver?

So this happened to me yesterday. It took me a while but I think I now know why. I ordered food from a nearby sandwich shop. It's within walking distance. I placed my order online and tipped. I marked for pickup and after placing the order it said my sandwich would be ready in 25 minutes. Cool. So I walked over to the grocery store first to grab a bag of chips and a soda to go with my sandwich. You see, the grocery store is a few doors down from the sandwich place- why pay more for smaller quantities at the sandwich shop, right? I get my chips and drink, put it in my bag and walk over to the sandwich shop. I walk in and the person working asks my name. I tell them and they say, "just gonna be another minute, you can wait here." OK no problem, I'm about 3 minutes early so I take a seat. I then watch another dozen or so people come in and order sandwiches. The person behind the counter takes my hot sandwich and places it on the cutting board. They then proceed to help the other dozen or so people while my sandwich returns to a room temperature (so much for toasting it). The person then finally finishes my sandwich 20 minutes after it was "ready". They put their "safety seal" tape/stickers on the bag and hand it to me. I'm not a Karen so I just take the sandwich and leave. All the while thinking, "that was rude, 40+ minutes to make 1 sandwich and even made me wait while I was there." That's when it dawned on me, did they think I was an UE driver and is that why they delayed/ignored my order for so long? Did they see my grocery bag and assume I was a food delivery person? I've been to plenty of places where I see negative interactions between the restaurant and the delivery folks.