This is in the grand tradition of not putting real numbers on a TV show. That's why nearly every phone # given out in a movie or the tube starts with the (mostly) fictional 555-prefix. Some people, will, indeed call numbers given out on a show just to see what happens. 

There have been a few who ignored the rule and people with those numbers have paid the price. Beachwood 4-5789 by the Marvelettes was one that comes to mind from 1962. Then there was Tommy Tutone's 867-5309, which some listeners across parts of North America called asking for Jenny. That drove those poor folks who were unlucky enough to have the number crazy. 

My guess about the one Wiz cites? It was a joke put in by the writers, who meant to take it out - and could have forgotten by the time it went to air. That's what happened to a cartoonist by the name of Wiley, who draws the syndicated "Non-Sequitur" strip that runs in the Toronto Star, among hundreds of other papers. The story of how "Fuck Trump" ended up being printed in newspapers across the continent is here. He put it in at the very bottom as a joke to himself - then forgot to take it out before it went to press. 

Some papers immediately dropped him for the error. Others, like the Star, are still printing it.