While true, the powers don't require you to attack adjacent enemies, my point was more the 'point' of using reach weapons. It's to avoid being adjacent to enemies, no?
I'm playing a fighter with a reach weapon right now, so I feel the pain on this one. Using a reach weapon has a "subtle" effect I've found. There are a few times when the reach has really paid off, such as when fighting a creature with an aura that did some nastiness to those who were adjacent.
And on occasion that extra square of attacking power makes the difference. However, most of the time i try to get as close as possible because combat challenge and superiority requires the enemy to be adjacent to reap the benefits.