Agree Billo, skills required to play basketball relatively well are far greater than that to play football, have you ever seen a non-basketball playing footballer take to a basketball court? Its not pretty, whereas it doesn't take long to get the basics of football down, it just a matter of speed and strength that separates the professionals in aussie rules. (there are exceptions of course such as Gary abblett jr who are exceptionally skilled)
Some friends that I would consider quite fit and athletic who play high level aussie rules for clubs will occasionally join in at local basketball games, but they often complain that while the court is much smaller than a football field, there is little to no opportunity to rest on a basketball court, you are always in motion, always alert of your opposition.
But I agree, that there are some NBL players that don't seem to realise that a professional athlete requires hard work on and off the court, whereas this seems to be ingrained in NBA clubs and PLayers, where getting into the league is just the 1st step, you have to work your ass off to get court time and be competitive.