I almost certainly attend festivals with mates older than you chaps. If you are particularly keen to catch Sabbath, you can always just get a day ticket.
I'm hoping to be on a dig in Jerusalem next summer, if that pans out I'll probably not get to any festivals, but hopefully I'll be at Hellfest where Sabbath are also playing.
That said, Ozzy is an embarrassment live now, and I know how depressing it has the potential to be...