Funnily enough when lanning was big 5 odd years ago- it was the exact same thing with lans and file sharing.. I'm mainly talking about Shafted- For those who don't know, was also run in Union hall.
It came to a point that file sharing wasn't allowed, this came mainly because of a few raids on lan parties in various locations because of the mass illegal file sharing.
That didn't mean file sharing was stopped.. it more just meant everyone had their DC minimized ;P
Its always been there and always will..
Lan parties obviously happened because of dial connections being insufficient to play games multiplayer. With broadband connections everywhere- there is more of an incentive to come for the leeching with all the caps and slow speeds of Australia's internet.
But gaming is still fun at lans
For me, things like more dedicated servers ready to go and perhaps more limited internet to allow particular steam games to work better to create a hassle free gaming experience!