These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Storing extra clips inside the stock, or somewhere else in the blaster, seems to be just a simple gimmick. Until you realize it's a children's toy that has a convenient feature that real firearms, airsoft/BB guns, and paintball guns don't even have. (ignoring that airsoft is justified in that they store batteries instead of ammo in the space.)
Amusingly, some of the carbine-style automatic blasters note The Stampede feature similar problems to ACTUAL gas-piston carbines, wherein a specific type of mechanical failure makes them shoot uncontrollably until they deplete their magazine. There's Shown Their Work, and then there's replicating an actual mechanical fault in real weaponry...
They Changed It, Now It Sucks: A certain breed of Nerf owners bemoan the transition from direct-plunger action dart blasters to the reversed-plunger blasters, and others weren't pleased with the introduction of electric-only powered Nerf blasters. With the launch of the Vortex disc blasters, yet more complainers are laying the hate on the different system.
The Rebelle Line has drawn criticism from some female Nerfers who think that Hasbro is trying too hard to market the dart blasters to girls.
Quite a few male Nerfers are complaining about them as well. The main complaint seems to be that their too girly for a Rated M for Manly sport like Nerf. However, some of the other common complaints include a reduction in firepower, accuracy, or just plain usability compared to other Nerf blasters for the sake form over function.