The idea is preventing a player from chatting with the rival goalie and just waiting for a shoot from the other side to magically be one-on-one. The main result is that half the team would be around the goal to prevent this, and midfields would be waaaay thinnier, becoming a "shot-try to score-deflect to the other side of the field-try to score-rinse and repeat", even more ridiculous that it already is sometimes.
Alternative bought Lv. 2 for me as a gift a few weeks ago :p I'm sure I'll toss in the extra $15 to go Lv. 5 eventually, but I need the activity level to justify it first XD Before yesterday I don't think I posted in over two weeks.