The fruit stand that you speak of has great fruit, but yes the owner is dishonest. Just know your prices per Kilo before you go to him to buy and it is hard to get ripped off. I personally do not care for the hole in the wall fruit shop left of the round about, not the best quality.
Also the guy at the "crooked" fruit stand has another dirty trick he likes to play. He will offer you all kinds of stuff to taste (grapes, cheese, ham, etc.) all the while his wife up front will punch it up in the register. I personally do not go to him anymore, not because he has fooled me, but I do not like to give my business to dishonest merchants.
Some of the best fruit stands are further into Aversa on Via John Fitzgerald Kennedy, just down from the train station, or even at the iperfamilia or appia centers . You can get to them from the first exit on the SS7 just past the Base.
For general stuff like pasta, Mozzarella, wine, cheese, sausage (not freezer food) I like to go to Marianno who has the little Salumeria at the "round about". He has a good selection of wine and also speaks good english.
There is another grocery store to the right on the round about, just down a bit on the left before the Pastaceria. Not always the best organized and the young girls are not shy about hitting on men, even with the wifey there!