More than half the Android devices I've owned had 3rd party app stores (sometimes more than 1) preinstalled. None of those stores got any use after a quick trial. The Orange OSF had it's own mail, maps, store and I forget what else, all instantly disabled.
People have this dream that replacing the Google framework and apps will make them irresistible to customers and wildly rich as a result. Most customers neither care or find the replacement efforts worthy. The minority that do want to avoid Google, install CyanogenMod and choose their own apps.
CM are free to try what Amazon, Sony (3 fscking store apps on my Xperia), most Chinese phones, every carrier and most OEMs have failed to achieve but it won't save their business because there are more blowhards pretending they hate Google than actual customers prepared to do something about it.