My guess is that, when XXX compares how much money he makes by running Gonzo,
he is probably making, significantly more money, by taxing the other studios' sales instead.
Combined with the fact that Porn production is a bit of a gamble,
meaning, they don't really know if the next movie will be in the black,
(we all remember that time when XXX said he lost money in seemingly 20 movies straight, right?)
He is probably thinking "running my own porn studio is too much hassle".
Seeing like that, Luis has to compete with the sales of not just IV and Giorgio,
but also, DDF, Bangbros, American Anal, etc, etc, to impress his boss.