UPS drivers are Teamsters (that includes the long-haulers, not just the drivers of those cute little brown vans). The drivers at my steel company were Teamsters, and my company had somewhere around thirteen plants in the United States. I’d like to see some data on what proportion of them are “port drivers” (including the ones who are afraid to drive internationally).
Keep talking. All your doing is proving you don’t know what you’re talking about. There might be a handful of contract drivers for UPS who are teamsters but it’s a tiny minority. My uncle has driven for UPS for 15 years and he’s not in a union.