Thats exactly what it is . Federal highway funding is what covers most of the road work , and states really need that money , especially for interstates , which see a LOT of cars moving through and requires extensive road work . As much as Id like to see the drinking age lowered since 21 is a stupid age I dont see it happening unless the federal government repeals the law that kills highway funding for states to lower the drinking age . Think about it like this . To change it you gotta vote . You got to be 18 to vote . Most people over 21 wont vote for it again , as much as I think the law is stupid , I dont want my taxes going up to cover the road budget , especially since im over 21 anyways because they wont wanna pay more taxes . The only people who would really support this are 1820 year olds , but they make up a small population . Besides alcohol isnt hard to get , I was drinking in highschool so no one really cares about lowering the drinking age .