Seriously. Try to do a join and some simple data manipulation/aggregation in Excel without this. Or try to emulate SQL minus/except. You'll Google for simple answers using the UI, and those probably don't even solve your exact problem, then dig until you find some that seem correct, try to implement them, and then realizes it doesn't work for some unknown reason. Then either give in and write VBA to do it (which also sucks), or pull it out of Excel and put in something that uses a good language.
In my experience, non-technical users don't want an outside application. They don't want to set up a database. They just want to open Excel, the program they are comfortable with, hit a button, and have their data aggregated. This tool is really cool.