Every time one of the guys starts dating the girls, the rest of the gang cheers for them.
Did they cheer when Soda and Sandy started dating?
Two-Bit and Kathy? (READ THE BOOK SHES THERE AHHHHH)
Dally and Sylvia?
Steve and Evie?
And not only that, but the gang likes watching the date.
For example, Ponyboy and Carrie would begin to kiss, then Carrie would hear Two-Bit laugh and the rest of the guys would pop up the the bush they were hiding behind.
...I suddenly laughed at the mental image.