I prefer to frequent CVS, Target, & Walgreens to do most of my shopping, but it doesn’t mean you can’t get good deals elsewhere. Sometimes I’ll just bring a couple coupons down to my local grocery store and save a few dollars here and there. It’s not always about getting the product at the lowest price, you also have to factor in convenience and the cost of getting there. For instance, I used to drive across town to Target for single items - this is obviously a problem since it probably was costing me more to get there in gas than I was actually saving on the product.
Regardless of where you shop, if you’re going to be there regularly, you should absolutely get familiar with the store’s coupon policy. You can typically find this on the store’s website or by asking for a copy of it from the store manager.