Emma tells Brent that Oscar is a really big fan of Neil Diamond. Later, when annoyed that Brent serves Wes before him, Oscar tells Wes "Money talks, but it don't sing and dance. And it don't walk." This is a line from the Neil Diamond song "Forever in Blue Jeans."
Wes Humboldt's father died in Korea. If this was during the Korean War (which presumably it was), it means that Wes is at least 51, 11 years older than the actor portraying him.