Even CCGs have a point of diminishing returns. A local store recently tried to do the 'CCG only' route (they had some sports cards and collectibles as well), they went under pretty quick...
Have you run a LGS? Where are your numbers coming from?
There problem then was the sports cards. They died years ago only to true collectors, and still are very few. I don't know anyone anymore that will even talk about sports cards. I really liked that gum though.
Also collectibles are a speculators market, just like antiques. You cannot expect them to turn over quick enough to pay for the overhead of having them in stock on the shelves.
Yes I have effectively run a LGS. Not the owner, but for all intents and purposes ran one or two,. well 4.
Those numbers are not things I would ever keep track of as it was not my business, literally or metaphorically.
Just simply put that CCGs will sell rather quick and moreso than a CMG ever could.
You could easily have different results in another area, but for this area that was the case. No matter what the CMG, sales were not that good, because the CCG market was so high that there was never enough space for both.
Of course you cannot run the store on CCGs alone, and have to have a more sustainable profit through other products, but just looking at the numbers of amount of CCG vs CMG sold, the numbers were vastly in favor of CCGs.
To the point of needing to buy 6 cases of CCG boosters per week and still not having enough on hand to sell, vs 6 cases of CMG per month and having to try to figure out how to get them to move in order to keep the shelves form stagnating.
So CCGs selling roughly 4:1 over CMGs is very showing numbers.
Not to mention the amount of singles for CCG selling much quicker than a CMG single, and for things like DDM that takes the same amount of shelf space as CMG and CCG with the cards needing to be kept track of the man hours to support selling singles meant little to nothing in return for them, while CCGs were really quick and took less time to work with overall and could be kept track of much easier without the need of matching part A to part B.
So CMGs are doomed in some areas for many reason, and you cannot own a store and hope to keep your head above water with JUST one type of game such as a CCG. You have to have other revenue, even though even on off pay-weeks people are apt to buy a single booster pack of a CCG to test their luck.
You also have to have a way to push sales of them both as well, and a CMG like DDM and most others are harder to push a single booster sale as they are hard to play "pack-wars" limited style gaming with. So you could easily offer some slightly reduced price for a pack or two of a CCG for a quick impromptu game a couple of times over compared to a single booster of a CMG.
Magic packs are roughly $4 now so $12 gets 3 packs which is a booster draft, while DDM only got 8 minis, and harder to drop down the same money on even for the minis-lovers when there was space provided the tables weren't full of CCG players and their 2-3 backpacks, etc.
The numbers are out there, just ask any LGS as a curiosity on how well they sell CMG vs CCG and ask which they make more on on average, and the CCG will be making more profits(%) per pack sold due to COGS and overhead such as shelf space.
