Story quests aren't endgame. Endgame content is what do you do when you finish leveling to cap, unlock everything, and then go play (usually with a slant towards combat content. Buying a house is generally not most people's definition of 'endgame'). Finish story, unlocked all dungeons/areas (heavensward areas in a month) and then see what you have left to do. Right now it's:
*Grind weekly tomes.
*4 coil bosses.
*WoD (before they unlocked fcob. Now you'd just do more fcob)

Think of a single player rpg. Many have an serious of trial beyond the story. Super crazy side bosses. Playing it again on higher difficulty, replaying with harder objectives for special endings etc. Endgame is AFTER the story.