Gary ... it is definitely not only worth while shopping your expendables, but your responsibility to do it. (if you don't who will do it for you?)
Too many of the things that are routinely purchased are not even considered as having any impact on our total cash flow. Personally or on a local state or fed government level...
The small things that you CAN control are the things that add up. Fixed costs in your life you can't do much with.
You can and will find differences from 10 to over 50 percent. Any one single item, maybe only a few dollars but that is not the only thing you will be buying. Do you do all your grocery shopping at a convenience store? Why not it's convenient, most things are only a dollar or so higher than at your local super market.
It is not hard today to shop price. Shop service and any other variable cost of living... The relatively small effort you put in pricing, will add up over the time you are a consumer. Economics still deals with the digits FOLLOWING the decimal point.
You can also get a bit of exposure to market trends if you stay on top of 'routine' commodities... again not hard to do with any type internet connection.
Save some money, buy what you consider better things and waste the extra cash as you see fit ...
Shop around. KennyV