Great.. All done now..

But still not sure how do stop the wall from showing attending members to events?

Hi, Niklas.

So you want to HIDE that activity on Activity Stream?
Then try to disable "Join Group" in Configuration -> User points.

That wont help me. Because its not the groups it is the attendence to events i want not to be shown. :)

HI, Niklas.

Oh, I'm sorry - my mistake. Then disable: Event Updated.
If you don't have this rule, make a rule scan (button at upper right).

If this will not work then... well, you'll need a developers help as there is no simple hack to do it.

Okay, that didn't made it either.. :-/

Hi, Niklas.

I just realized that I misunderstood you from the very begging :/
I'm sorry about that.

If you want that main Activity Stream doesn't show that certain users attend an event then:

Copy that file: ROOT/components/com_community/templates/default/activities.events.php

to

ROOT/templates/your_current_template/html/com_community (if you don't have "html" or "com_community" folders then feel free to create them.

Then edit activities.events.php in line 24:

<?php if( $this->act->app == 'events.wall') { ?>
		<?php $this->load('activities.profile'); ?>
	<?php } else if( $action == 'events.create') { ?>
		<?php $this->load('activities.events.create'); ?>
	<?php } else if( $action == 'events.attendence.attend') { ?>
		<?php $this->load('activities.events.attend'); ?>
	<?php } else { ?>
	<?php
		$table = JTable::getInstance('Activity','CTable');
		$table->load($this->act->id);
		if(!$table->delete()){
	?>

<?php if( $this->act->app == 'events.wall') { ?>
		<?php $this->load('activities.profile'); ?>
	<?php } else if( $action == 'events.create') { ?>
		<?php $this->load('activities.events.create'); ?>
	<?php } else { ?>
	<?php
		$table = JTable::getInstance('Activity','CTable');
		$table->load($this->act->id);
		if(!$table->delete()){
	?>

YAY!
That made it. GREAT.

So much thank you for your help. :)
Even though it was a long struggle. ;)