I do this! The only frustration is that sometimes when you make arrangements to fly, the weather or unserviceability stops you. There are three people I take flying regularly who can't really afford to fly on their own for various reasons, and I remember when I younger I couldn't afford to fly either, except occasionally with the air cadets or a bit of gliding once a year. I fly people whenever I can, providingthey are prepared to pull their weight to the extent of their abilities. At one end that might just be looking for traffic and helping wipe off the oil afterwards. At the other end it might be a great deal more participation in the flight. I'm not an instructor so I have to set limits. But I don't like to fly a two-seater with an empty seat if I can help it.
At least one of those people I am certain is going to be a GREAT asset to aviation in this country, and we will all benefit from having that kind of person as fully involved in aviation as possible in years to come.