[H] video plug ins on a receiver

[Winterlight]

 I haven't cared or paid any attention to audio setups in twenty 
plus years. I have sound bars on my TV... but that is all I need. I 
was given a old  Sony STR-DE345 Receiver 
http://www.crutchfield.com/S-YcStDQVeLrZ/p_156STRE345/Sony-STR-DE345.html 
. It is in pristine condition. I am only using it as a headphone amp 
for my TV. This 5.1 A/V receiver has plug ins for VHS, DVD with 
yellow RCA composite video plug ins but why video ... why does it 
have composite video plug ins on a audio receiver ?... I don't get it?