Foo Fighters brought KISS’ Gene Simmons out onstage when they played Las Vegas last week, and Simmons humorously handed Dave Grohl a cash tip. That’s what appears to happen in fan-captured video of the quick encounter. And for a musician such as Simmons, who says he makes money at an Olympic level now, dropping a buck is apt praise. The moment was ripe for some sort of KISS and Foo Fighters team-up, anway, as Grohl recently covered KISS’ “Rock and Roll All Nite” with producer Greg Kurstin for the pair’s 2021 “Hanukkah Sessions.” See the footage of the Foo Fighters-Simmons summit down toward th…