改同意句! why not have something to eat? =whai about something to eat?

why not 为什么不 ? = what about = how about ...怎么样

这个地方 what about = how about

吃些东西怎么样?

why not=what about=how about
why not后接动词原形
what about/how about后接名词/动名词

你的是表建议的委婉表达方式;
why not + do sth = what about doing sth = how about doing sth...

所以应该改成:
why not have something to eat? =what about eating something?
or how about eating something