Why do people think it will be poorly attended? Leeds is the biggest rugby league city in the country, it's geographically the closest Magic Weekend ever to Hull, both of whose teams always take decent support (albeit usually to watch a derby which isn't the case now), and Leeds United are probably the best supported football club amongst rugby league fans east of the Pennines.
The Saturday at least should be very well attended with the biggest game of the weekend taking place on the same day as Leeds are playing and a likely sizeable following from Hull FC will be there too. There's a very good chance the clubs playing on that day could sell out Elland Road between them.