In your quote, the meaning of *provide for* is *to act to prepare for something* (Wiktionary, [verb sense 2][1]). 

We may rephrase the quotation this way:

> It turns out that there are contractual answers as well: creditors can **prepare for** these possibilities in advance, not between themselves but by taking security interests in your assets—in other words, a right to take back your property directly if you run out of money. 

Let's look at an example sentence:

> The architect **provided for** (= *prepared for*) the possibility of storms by strengthening the abutments.

If you substitute **provide** in the place of **provide for**:

> The architect **provided** the possibility of storms by strengthening the abutments.

the resulting sentence is absurd: stronger abutments are somehow supposed to invoke storms. 


  [1]: https://en.wiktionary.org/wiki/provide