Been wondering

[Wilson Gray]

Is anyone familiar with constructions of this type? I've heard them
only on television, spoken by whites.

"So, what's he [your boss] gonna pay? Two people to do the same job?"
Wife to husband bragging about his having been given an assistant,
whom he will be training.

"What're you gonna buy? Two copies of the same magazine?" Overheard at
magazine stand.

I would have expected "... gonna do? Pay ... / ... gonna do? Buy ..."

-Wilson Gray