If it was as simple as pressing a few buttons, why would characters make a big deal of "real" food being superior in taste? Anyone who wanted genuine-quality food could get it for the cost of a few extra keystrokes!
Because if they can store 25+ recipe patterns of perfectly adequate quality @ molecular resolution, or one (1) superior (transporter-quality) pattern for just one dish... they'll take the 25+ options.
Even in the 24th century, computer memory isn't infinite - look at what happens when they have to store Sisko, Jazdia, Kira, Worf and O'Brien's transporter patterns in computer memory in DS9: "Our Man Bashir." They have to wipe most of the station's memory to do it! There simply isn't the "hard disk" space to waste on going to the quantum scale on a chilli con carne.