"Rebates, preferences, and other discriminatory practices in favor of the combination by
 railroad companies; restraint and monopolization by control of pipe lines, and unfair practices
 against competing pipe lines; contracts with competitors in restraint of trade; unfair
 methods of competition, such as local price cutting at the points where necessary to
 suppress competition; [and] espionage of the business of competitors, the operation of
 bogus independent companies, and payment of rebates on oil, with the like intent."