Ace Hardware

I have been painting all of my life and understand the difference between eggshell, flat, simi-gloss and gloss paint. I started painting my laundry, closet and bath using a good quality Lowes paint (eggshell). I ran out and needed to go to our local Ace Hardware to get a matching eggshell. After the paint dried it had a shine to it and not at all like the first can. This can shows eggshell but there is something wrong with it, it is NOT eggshell. I took the can back to my local store and the owner stated that it is because of the different brands. I felt insulted because I know paint! He could not offer me a solution that is why I am complaining to you.