。
She's not rich enough to throw money around.
Literal
She [topic-は] money [object-を] can-squander [to-the-extent-of-ほど] rich is-not.
The frame [verb potential]+ほど~ない ('not as ~ as can do X') uses ほど ('extent') to set the threshold and negates the predicate to claim that threshold isn't reached. 浪費する ('to squander, waste') has an explicit pejorative weight — the prefix 浪 ('waves, frivolous') carries the connotation of careless overspending. The corresponding noun 浪費家 ('a spendthrift') goes with the productive ~家 suffix for a person characterized by the activity.