[sAmI]

phpbb and mybb need to be written from scratch honestly, the arabic support is so weak and most decent themes dont work with arabic language unlike xenforo,i have tried all forum software except tribe.
i added flarum and NodeBB are free have so nice ui but sadly need composer which sucks.

answering your question why i use nulled scripts
1- im not greedy if i can afford it i would have bought it and maybe this goes for all the people who use nulled scripts 
if they made revenue to cover the cost why not just buy it and avoid the "risks" of using nulled scripts ?

2- actually xenforo and vbulletin got so famous because of the nulled releases from GYSN and DGT teams if any one remember so actually nulled users making the script more famous and more customizable

3- so i can hoist the pirate flag

As far as i remember MyBB does have good support for arabic though. Using Nulled Software causes problems for the creator and for the VPS which you are using it for.
For example : If you use TeamSpeak3 Crack Licence they will ban your VPS IP, Now just think that ip remains blacklisted forever, And the VPS company gives the IP to other buyer and he want to host TeamSpeak? 
I used heztner and i hosted my teamspeak3 i use to get so manyyyyy blacklisted IPs, You cannot do anything for them.
I'm not sure what action other companies take, But it also creates issues for the hosting side. The VPS provided by P4V are almost equal to paid ones!