MAC Dupes!

Heya!
I was perusing some of the things I have neglected in my ever growing stash. I don't know what it is about makeup which makes even the most scholastic in the art of colors go ooh and ahh every time we see new makeup. There are only so many shades of yellow, red, and blue with a bit of black and white right? So....why is it we run top speed to the makeup counter for the latest, newest green, pink, yellow, taupe, etc.?
I'll admit I'm suckered on a constant basis. Take MAC's latest Makeup Artist Cosmetics launch. I needed nor did I want anything from that line. So, why do I have a picture of Photorealism? Because there was a green that was not similar to any other green MAC released. So, off I went to the nearest counter to drop some money into my part of stimulating the economy.
Well, then I was looking about my non opened buy one get one's from Maybelline and would you look at that? I am hard pressed to say with that quad on the right, you cannot come up with similar colors from the quad on the left. I haven't opened the Maybelline, as I think I will gift it to another makeup addict. No reason we both should be out $$$ due to our addiction.
Here's another example. I have three bright pink lipsticks. From left to right: Rose Hip by Milani, Show Orchid by MAC and 511b by WnW. I am by no means a photographer and I don't claim to be good, but the pictures tell half the story. These lipsticks are within a shade or two of each other. They are placed from lightest to deepest in terms of the amount of red in the pinks. Again, if you select the Milani and added a hint of the WnW, you would have an exact duplicate of Show Orchid. I am so frustrated at my learning experience. But, hats off to those of you who have learnt the art of using what you have and making it work. Affordability is key if you are on a budget.
xoxo