I'm just surprised is all. If someone throws stones they could probably throw them farther and harder if the stand up. I'm not saying you're wrong but it sounds a bit odd. Also, by stand I presume you mean the shed behind the goal. That's where most fans congregate. So throwing stones from there would have been kind of stupid too since chances are you'd hit other Limerick fans - especially if you're sitting down - because I have never seen everyone in the shed sitting at the same time.
Also, if something like this happened (and I would condemn it unreservedly) why wasn't it raised immediately after the game instead of waiting for a Dundalk fan to prompt it. Maybe it happened but are you sure it wasn't all a bad dream? :)