Singles Where the B-Side Also Charted

[Boogiedown]

In 1972 DJs flipped MOTHER NATURE by The Temptations enough that "Funky Music Sho Nuff Turns Me On" charted #27 Soul.

Also:
By having big songs released one at a time you extended the amount of time the act was on the radio , putting them into the ears of their concert going fans over a longer period.
And fans would now be tired of one song and ready and eager to hear [and buy] the next and newer one.