Ali110 wrote:
How is it going to be determined the lucky few who get to stand?

It's not.  This isn't an option which is why I'm trying to figure out what to do.  But, the weddings I've been to that have done this, table seating is basically first come, first serve.  I've even been told by wedding planners (who I'm not using) not to have enough tables for everyone to sit because you want people to mingle and dance and not just sit the whole time. 

It's ridiculous, I agree with all of you.  But everyone keeps telling me "oh only half of the people you invite are going to show up" but I'm finding that's not necessarily the case.