Every time any of my sims have a visitor, whether it's someone who just stopped by, was invited over, or came over for a stay-over, the visitor goes straight for the fridge and makes a white cake. During a stay-over, 3 people came over and all three of them were constantly making cakes. It doesn't seem to matter what household I'm playing - it happens with all visitors unless I keep them constantly engaged and then send them home. If the visiting sim is idle for ANY length of time, they're right in the fridge pulling out the ingredients to make a white cake.
Edit By Crinrict: Adjusted Title fit bug report at AHQ
