A lot of companies still do all the processing on text files as a nightly run (particularly those companies getting once a day data files (e.g. credit card rewards processors)). Some put it in an actual database, but you can really churn through text files faster than a lot of relational databases can do their queries.

The most interesting example I saw of this was a company that had an automated process to add a header with time/date/source and check it into code control (subversion I think). The nightly batch job checked what it needed out and did all the processing including generating some control spreadsheets.