The "ChicagoJim" household as mixed feelings about Mariano's. Mrs. ChicagoJim loves the place, I don't.
Why don't I:
Some stuff just never comes back. When the South Loop store first opened they had an amazing display of Polish goodies - ingredients, candy, chocolate, etc. It all got sold and was never restocked. Clearly, there was a demand as it was purchased.
Some stuff is a one-off: A while ago they had Hudsonville Ice Cream, unheard of in Chicago in my experience. Then it was gone and never came back.
My mantra is "Never buy anything that was once alive." The produce is horrible and often rotten and seldom fresh. Mrs. ChicagoJim recently brought home a bag of yellow onions that were rotten. The displays don't look appealing. The meat is questionable at best, and sometime does indeed have a bit of funk. I'd never buy seafood, ever. Never buy the produce in the big bins when you first walk in, that's always going to be rotten when you get home.
The display of bulk spices is/was tempting, but then you'd wait 20 minutes while they scared up someone to help you, who then didn't know anything about the spices and couldn't really help you. One time I was buying something very light and the scale wouldn't ring it up. That caused a 30 minute round of confusion (which would have been amusing except I just wanted to be out of the store by that point) until someone just had the good sense to say "how about we charge you $0.75 is that OK? After saying "sure" they then couldn't figure out how to get the pricing machine to force that price out to a label.
The cheese area has very tempting displays of what are mainly very pedestrian selections, and I have no confidence that the cheese has been stored and aged under proper conditions. In all fairness, WF has the same problem - buy the exact same cheese at WH and Pastoral and they taste completely different.
Cashiers have gotten a bit better, but at the beginning they didn't know the difference between a green bean and a chili pepper! It was like they found them on the street gave them no more training that in how to scan barcodes and turned them loose.
They don't stock odd things. Last year we were going to make the family recipe for corn bread that involved creamed corn. They didn't have any, and looked at my like I was an idiot implying that such thing existed.
I do like a few things on the hot bar. The Mac&Cheese is better than I can get at Whole Foods for a lower price - probably because Mariano's makes it with all the stuff the WF has decided is "bad" for us. And, the do have the largest selection of frozen Pizza I've seen anywhere - although the Stouffer's French Bread pizzas have also disappeared from Mariano's, but that's a different thread.
So, bottom line? I'll stop in once in awhile for something I need quickly that isn't produce or meat, dairy and frozen seem to be OK.