Two of my friends who had retired in the early months after the game's initial release tried to come back to the game. They both had really high hopes and were very energized over the idea of rejoining the community and even were ok with paying the subscription fees.
They both quit again after a week of playing because neither could find anyone in the low level ranges to form a party anymore. Sort of a product of low server population in addition to everyone being max level in basically everything by this point in time.

Sure, we could have exploited the claim system to power level them up, but some people play a MMO for the journey not necessarily the numbers. And if you can't participate with your friends (or make new ones) through out all aspects of the game, what is the point of playing a social game at all? I know that the dev team has promised us a level sync system in 2.0, so I just wanted to highlight the importance of it if they expect to to have capped people and new or returning people coincide merrily.