No,you are wrong. They quit because they are not getting what they paid for. That is entertainment. The game is not fun enough for people who quit. There are many reasons and one of them is the widening gap between players. You need to take some economics reading to understand the difference between value and price. It doesn't matter if it's skirmish, delve or just sitting around playing with mog gardens. Casual people are getting less value than hardcore players. They have no access to delve content and can not participate in events that take more time. Therefore they have no access to better reward equipments. Maybe some people still have fun but FFXI is having people NOT HAVING FUN. That means some people realize they are not getting what they want for their money, time and effort => they quit.
On your club example: that's why some people don't go to clubs. Think about it for a second. Clubs serve a particular class of customers, they know they need to get the men in by getting the ladies in. The ladies attract the men. That's why you get clubs with free entry for hot ladies. Does FFXI serve a particular class of customers like the hardcore players? Should it be a super hardcore like the olden days with LS points, ultra rare drop and sadistic wait timer? OR do hardcore players realize that they actually need casual players to help move the game along and therefore should have SE give free access to casual players (i.e. like free to play games).
If you put effort and time into something then it has real worth no matter what it is. It can be anything from random piece of imagination to the largest construct in the world. Virtual item or no is irrelevant. It does not have to exist for it to have any worth because the value comes from the person placing it, not the item itself.
Stop thinking about 'this is the right thing'. There is no such thing as the right thing in business, only success and failure. Also, what was a success yesterday can be a failure today. Putting hardcore players on top is the failure at the moment and it is showing.