DR is insanely spendy, and their loyalty program blows. Rite Aid is by far the cheapest drugstore in the city. Are you not buying store-brand? Shame! (Never buy store-brand tampons, though. Lesson learned.) Check out Jack's 99-cent store (45th St seems to be the nicest)for some of these things. It's not 99-cents, but it's damn cheap.
I've only seen Mason jars at the Jack's on 40th Street (by the library), and Amazon offers jars and rings on Prime (free shipping!) usually. Also, if you need sassier jars, Fish's Eddy has some adorable ones.
Not only do the charities only receive a small percentage of your donation, you're rewarding their canvassers occasionally repugnant behavior! I don't have any time for someone standing in my path, trying to grab me. Look into the company you work for; many match charitable donations. Then you can properly vet the charity on your own time, and give the charity of your choice much more money.