A week joke at best

Jack Applin writes:

“When Labor Day falls at the end of the first week”? Where does Frazz take place? In the United States and Canada, Labor Day is the first Monday in September, which isn’t at the end of a week.
https://en.wikipedia.org/wiki/Labor_Day
https://en.wikipedia.org/wiki/Labour_Day_(Canada)

I’m guessing that what Mallett means is “When Labor Day is on the 6th or 7th of September”, i.e., near the end of the first week of September. But I still don’t get the joke even if that’s the intent.

Where we’re going…

…they don’t have roads?

Jack Applin writes:

I was puzzled by the “off-road trim”, because cavemen don’t have roads. Then I recalled “Dip in Road”. OK, fine. Why would the triangular wheel cause political arguments? It’s not pink. Is it simply “That other political party is so stupid that they promote triangular wheels! Haw haw!”?