This is way too philosophical for me, but I am pretty sure that Georges Braque called Picasso a flopper on his twitter stream.
Complain about what? They don't complain on the court more than most. Your boy Bryant complains about EVERYTHING. He perpetually looks as if somebody's crapped under his nose. If you're saying that their agents make demands more than most - maybe. But their agents would be bad agents if they didn't, because those players typically have more leverage than most. They really would get paid more if they stayed in Spain (in most cases - not Gasol's now, but I don't recall Gasol actually complaining as much as most American stars would in his shitty situation in Memphis. And if they didn't complain, it'd be because they were okay with an organization that didn't care about winning.)