Seems to be much ado about nothing. If a piker bothers you, don't group with them again.
At any time, any single person could have a RL issue to attend to. No biggie.
Also, sometimes piking may be the best option. Imagine being in a newb group (that is performing well) in Wiz King and someone falls through the floor. It is better for that person to get to the middle rest area and pike for a while and then rejoin the group when the group is done with a tower as opposed to waste everyone's time coming down so everyone can hold hands together in the quest. I can think of lots of in-game examples where someone piking around for a while is the best option when the group gets separated.
Problem is that if people don't know the quest, they could totally misinterpret that decision to 'pike.' That itself is a good reason NOT to have a 'report piker' option.