Baby wipes have moisturising agents in them which keeps the leather supple and looking new. Admittedly they were designed to scrape shiite, clean and moisturise a babies arse all in one wipe, but your leather seats used to be a cows arse (with the exception of all the plastic, sorry, synthetic leather parts), so they'll do the same job on that too.
My leather seats in my Passat still look pretty good considering they are 8 years old and been sat on for 106,000 miles. They've been cleaned with nothing other than baby wipes.