Did you know that many popular movies have sequels that few have heard of? From "Road House" to "A Christmas Story" to "Mean Girls" to many, many others. More often than not these are TV productions or straight-to-video releases. Thank G-d for that.
Take "Midnight Run". The 80s classic starring Robert De Niro and Charles Grodin (Jew; raised in an Orthodox family) is a staple of the first-they-hate-each-other-but-they-grow-if-not-to-love-than-to-understand road trip genre (other examples include Martin/Candy, Downey Jr/Galifianakis, Rogen/Streisand and Beavis/Butthead). De Niro is a cop turned bounty hunter, Grodin is an accountant turned embezzler. Our old friend Yaphet Kotto has a major role as an FBI agent trying to bring them in.
The movie works because of the interplay between De Niro and Grodin, so it makes sense that neither of them returned for the sequel. De Niro was replaced by the schlocky Christopher McDonald, Grodin by Jeffrey Tambor (at least in the first sequel. There are two others. Yes, there are THREE sequels to "Midnight Run"!).
Now, to be fair, we haven't seen any of these. Who knows, we might be pleasantly surprised? After all, they could be no worse than mainstream drivel like "Caddyshack II". Or "Rocky V". Or "Speed 2". Or "Batman & Robin". Or...