我把as...as...比较结构去掉，简化句子：

1. There is still much reason for her to help the charity as often as possible.

2. There is still much reason （there be 存在句，reason 是主语）for her to help the charity as often as possible.（不定式复合结构，作定语修饰reason）

3. as...as...比较结构，用于now （现在）和 ever （过去以往）的比较，现在插入句中：

由于第一个as 是程度副词，修饰much，所以要放在much之前：as much，而much 修饰reason，再把now 跟ever比较。

There is still as much reason for her now as there ever was to help the charity as often as possible. 

There is still as much reason for her now as there ever was to help the charity as often as possible. 

如果省去句末的as often as possible, 句子结构就可调整为：

There is now still as much reason for her to help the charity as there ever was.

不定式复合结构为reason的限制性定语，按理比较分句应该位于不定式复合结构之后。但原句中的不定式本身有状语as often as possible. 如果将as 比较分句放在句末，就会出现 as often as possible as there ever was. 即as比较分句与另一个比较结构混合在一起了。这会引起 as possible as there ever was 的误读。为了避免歧义，使句子结构清晰，作者不得以，将as比较分句插入到不定式和其逻辑主语之间。这使得不定式结构看上去很复杂。但只要仔细分析，其逻辑关系还是比较清楚的，不会产生误解。