Instead of using coupon codes that some people do not know about and therefore don't get the benefit of, SteamMonkey built a 15% discount in his prices so you don't have to enter a code to get it. It's calculated in the "add to cart" price already.
Not entirely accurate lol.
I price the vast majority of my items based on a formula I've got that generates enough profit for me to cover my time/effort and to build on my development stuff that I'm working for future items. My formula just happens to put my prices lower than a lot of other folks, some items are more expensive than other folks, etc. Theres no undercutting, no sales, just prices.
Because my prices are relatively low I don't usually run coupon codes or sales. I will, once in a while run a sale but it's targeted to move a product for various reasons (say I buy X, and Y from the same vendor and Y is getting low but X isn't, I might put X on sale to move some so I can justify the restock of Y and associated shipping/processing costs).
There are a number of tricks retailers use (not just ecig retailers) and are sort of stock in any retail education material you might read when starting a business.
x.99 prices make people think it's cheaper, i.e. 14.99 is less than 15! Yeah, I don't do that. I feel it's insulting to my customers intelligence (and it makes numbers more complicated on the back end

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Inflate your prices to cover shipping costs then offer free shipping! Another one that is overly complicated on my end and not worth the hassle. I just mark the stuff based on my formula which comes out pretty decent price wise and you pay for the shipping. You saved gas and time driving to a retail outlet (and probably money) so the shipping shouldn't be a big deal
Inflate your prices by X% then have a coupon code for X%. I dont' do this either, it's artificial savings and transparency is a huge part of my business model. It's why I tell you when I find a flaw with an item, mark my 'knock offs' as such and explain why I carry them, and why I openly talk about my pricing structure and shipping practices.
I figure if I'm honest and transparent, people will never feel scammed or taken advantage of. Go in educated with your eyes wide open and there should be no surprises when dealing with me. (outside of the random chinese QC issue

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