To add to the existing answers, Beatrix is not shown to care much about money at other occasions:
When leaving Budd’s caravan, she does not take the suitcase of cash, even though she very likely knew of it’s existence:
Beatrix sees Elle arriving at Budd’s caravan and directly attacks Elle as soon as she leaves it. Given the length of Budd’s and Elle’s encounter, I would strongly expect that Beatrix could eavesdrop on at least some of it thus getting to know that there was possibly a considerable amount of money in the van.
Moreover, after Budd’s demise, Elle was collects the money in a manner that does not suggest thoroughness. Therefore it is likely that she left some bills around in the van, which could have hinted Beatrix at the fact that there was a great amount of cash to be had there.
Even after she killed Bill, there is no indication that she plundered his house, even though it is plausible that there are some valuables to be found.
So, either Beatrix has access to a hoard of money somewhere or does not want any, even after she learns that her daughter is alive and there is a life after her revenge.
From an out-of-universe perspective, Kill Bill is an homage to certain grindhouse action movies and caring with such detailed procedures as looting the bodies would just seem out of place. It’s very far from the main focus of the movie. It’s comparable to the fact that you hardly see anybody going to the toilet in movies, except if it’s essential to the plot.
