What are the typical uses for a non-inverting quad buffer IC?
To increase drive capability. A microcontroller I/O pin might only be able to source or sink 8 mA (for example). A buffer chip might be able to source and sink 64 mA.  If we want to drive a long wire, or have large fanout to many receiving chips, the we have a large capacitive load and we might need to use a buffer to maintain fast rise and fall times.
For robust receiving of off-board signals. The buffer chip may have higher gain, so be able to receive signals coming in over a long wire, even if that wire attenuates the signals significantly. The buffer chip may also have more robust ESD protection than a microcontroller or FPGA I/O, in which case using it also provides some reliability improvement over connecting directly to a complex circuit.


Of course you need to compare the relevant datasheets in your circuit to see if either of these scenarios applies.