Originally Posted by
Tsukino
Other people already did a pretty good job of explaining how it affects their gameplay.
If you want to level legitimately, the pool of other people for parties matters quite a bit. If only a percentage of people want to party without power-leveling, then you have only that percentage to work with. If everyone is instead forced to gain experience with those around their own level, then your pool is much larger.
Beyond that, there is also an issue with "campsites" and how people use them. If some level 50 characters are slaughtering level 30 targets, they've monopolized the whole place. If that wasn't useful for something, it would be free for people to gain EXP in normally - perhaps even more than one group to do so.
Finally, there are the hazier concerns about game balance and sense of accomplishment and such. In some games reaching the maximum level is a major achievement. Even if it is difficult to do without power-leveling, the option lessens the sense of accomplishment because they "could have just done it the easy way." Overall, with rising in level being very easy, you also end up with a game that has a pointless grind followed by content, rather than the RPG ideal of content alongside progression. Basically, the population influences the content and if everyone is max level due to power-leveling, why would the developers bother making content for level 30 players?