It is being a bit picky in my opinion but the issue is that if this pattern continues deployments could take x longer depending on how long each gem needs to be installed. If the gem isn't required for your app to run why should you wait for it to install? Also in some more secure orgs certain gems need to go through an approval process. If this has become a dependency it could create an impasse as you need to go through all the hoops to update artifact repositories etc.