It isn't even that it is necessary for heroic raids. It isn't a major issue though. Just avoid pushing it and don't anger guild officers to the extent that they want to inflict pain on your guild before they leave.
The second one sounds like a guild problem rather than a game problem. And accidentally quitting a raid is user error. The dev's shouldn't be expected to hold your hand against guild problems or user error.
And you haven't considered opportunity cost. Any development time (however small it may be) that is spent removing a button that does not need removed is time they aren't spending giving us new content or fixing bigger problems.
I don't know how much more time it were would take to remove the button only for heroic raids but it is probably all coded together since that would be what makes sense since the feature is the same for all tiers. And removing it fir all tiers is not a good option since it would hurt newer guilds. And it would almost definitely take up more time to separate the code for the button. More time than it is worth.
I'd rather get many other older features. Maybe a sim for the hat for example would be better than this. Or for them to focus on their new game mode so we get it sooner or with less bugs.
