I find that 'item' in the URL handy....I can use it with the nonumber custom module it exclude modules from that level...
So, I can set a module to display via the social network link on the menu...then exclude it for actual groups/events by using their URL 'exclude' option, where the module won't display if it detects a specified part of the URL.
"item" is a good word to pick out for this purpose....
see where you're coming from with SEF though....at least ES uses a proper url with the title....last time I looked, Jomsocial was still using non SEF urls for it's events!!