Can Restaurants Even Be Profitable?

It has been some time since I played restaurants, so it might have become messed up in one of the patches (not unlikely), but I was able to have several profitable 5-star restaurants. It takes a lot of investment, you need to keep offering your staff trainings - and promote them to keep them satisfied. Help out with cleaning the dishes, this'll free up one of the waiters for other tasks. Also, I've found the best thing is to have one chef station, two waiters and 6 or 7 tables accommodating various party sizes (although, I don't think I've ever seen more than 4 Sims come in together). Don't have anything that distracts customers, no radios, no tv's, certainly not a bar. Keep your restaurant open for about 8-9 hours, but disallow customers at around 6 hours after opening. From that moment the game will no longer send new guests, the ones that are already on their way at that point will still arrive and ask for a table.

As for it taking too long before customers can eat and pay - open your restaurant before travelling there. Once you get there, one or two tables will already be occupied and ready to order/awaiting their food.

But I'll fire up that old save and see if running a restaurant is more difficult now.