Need help StarCrash and StarCrash 2 ship

[Treadwell]

Just look at this ship the model maker made for other scifi movies around the same time:

Given the two-day deadline he did a remarkable job, but what's his excuse for using sprues for this one?

 

[Contec]

Given the two-day deadline he did a remarkable job, but what's his excuse for using sprues for this one?

Maybe he read somewhere that starwars ships used modelparts on the ships.