Back then the oil/transport companies started using security details in unmarked cars trailing the tankers around.
Sales of locking gas caps soared
I worked my way thru high school pumping gas from 3 to 9 pm. I did my homework inside that little shack on the center island between customers. $2.55 per hour. 1975 to 1977. The gas craziness was more around 1974 and 1975. It mellowed out by 1977. Went above a dollar in 1979. The little meters had to be tweeked to .13 per gallon to record $1.13 on the displays. It was nutz.