Haha, I love this question! No, typically Pharaohs did not sit on their thrones all day.

Pharaohs were not just symbols of monarchy like some societies. The Pharaoh was also the army general and the high priest of Egyptian religion. The Pharaoh was much more than a divine figure; he or she was supposed to be the literal embodiment of a God on Earth. As such, it only made sense that they would be very direct rulers.

Pharaohs could have strict schedules, much like a President would today, and some would make time each day to meet with their subjects to listen to their grievances, etc. If an Egyptian had a problem they couldn't solve via legal or magical means, they made a trip to the Pharaoh. Cleopatra VII was so popular with her people on this account that whenever she traveled across the country, she had to declare a day of general amnesty simply so she wouldn't be bombarded by requests from people.

So to answer your question: yes, Pharaohs did sometimes lounge around on their thrones and do business there. They also, depending on the Pharaoh (of course), could be incredibly dedicated workers. The issue, I believe, is that they partied even harder. You can imagine why the day-to-day business of being Pharaoh wouldn't be as interesting to show in a movie as the parties and throne-sitting.

The text below is from Cleopatra: A Life, which I've quoted so many times, but it's my favorite for a reason. It's a description of what Cleopatra's day may have been like, based on the daily schedules of previous Pharaohs. I can find the Diodorus text she's referencing if you're really interested.

Greek historian Diodorus outlined another first-century sovereign’s schedule, some version of which would have been Cleopatra’s as well. After being awakened, she waded through sheafs of dispatches from every quarter. Her advisers briefed her on affairs of state. She corresponded with high priests and fellow sovereigns. If they were well, if their public and private affairs proceeded satisfactorily, then—went the formulaic greeting—she was well. She handed down decisions. She dictated memorandums to various scribes and signed off—sometimes with a single, powerful word meaning, “Let it be done”—on others. Only later was she bathed and dressed, perfumed and made up, after which she offered smoky sacrifices to the gods. At some appointed afternoon hour she received callers, on state, temple, and judicial business. Those audiences could be stultifying; they had lulled an earlier Ptolemy to sleep. Cleopatra’s responsibilities very nearly rivaled those of Isis: She not only dispensed justice, commanded the army and navy, regulated the economy, negotiated with foreign powers, and presided over the temples, but determined the prices of raw materials and supervised the sowing schedules, the distribution of seed, the condition of Egypt’s canals, the food supply. She was magistrate, high priest, queen, and goddess. She was also—on a day-to-day basis and far more frequently—chief executive officer. She headed both the secular and the religious bureaucracies. She was Egypt’s merchant in chief. The crush of state business consumed most of her day. And as that early, weary Hellenistic monarch had acknowledged, absolute power consumes absolutely.