You can only ride the cute train so long - trust me.
I take an adorable 2 year old with me and a lightening sharp 5 year old who oozes charm, but after 20-30 minutes of the cashier having to hear me constantly yelling "sweetheart stay with mommy", or "keep your hands to yourself", or "look with your eyes not with your hands", or "HOW MANY TIMES DO I HAVE TO TELL YOU TO STOP TOUCHING STUFF", even the most even tempered of people get abraded. You just wait until she's too big to ride in that tiny cart and then you let me know how that goes eh? I usually get all kinds of really good deals and then have to pay full price for the candy my kids break open during the lengthy checkout.
Have coupons, will travel.