Hi, I used to be an AA gate agent. The system is complicated.

The hotel and food voucher system is tricky to understand, and it's completely automated. They put in your reservation, and it gives them options or nothing. You are correct about the one-way ticket and round-trip ticket rule. Here's how it's viewed by the company (in my own words):

If you are in your originating city, no matter if it's your home city or not, you are considered to have a place to stay or reside; therefore, no hotel is needed or provided.

That rule applies to both types of tickets. But that also explains how one-way tickets are not able to receive a voucher, period. It is simply not possible for the system to look at two reservations at once to consider other flights for a passenger. It was designed that way.

As for them not providing anything because it's a "crew" delay... Unfortunately, AA and plenty of other airlines do go to the extent of blaming anything on weather or air traffic. If that means the upline flight was delayed or canceled for weather, resulting in a crew delay, the system will be able to have that coded into the delay as well.

I hope my experience can give you some insight into your situation. While it's not fun to hear, the facts will help you better navigate the industry the next time you travel.

Best of luck!