We have determined that this glitch seems to occur only when the game is actually running (and you're keeping an eye on things LOL). When the game is off (or you use Time Warp), the peeps' ability to earn money operates more normally, since different parts of the programming are involved. Also, purchasing a career upgrade from the store can make things start working properly again when the game is running. It's a tricky bug, but we'll figure it out!