Just a recent meme trend. However, I will note Nascar has union attempts deep in its earlier days that were even supported by Jimmy Hoffa.

I think it's also partially about taking something that can be associated with ... rednecks/middle America/conservatives I guess, and using it as a vehicle to try to reset people's initial reactions against stuff that would be in their interest (unions for example). It doesn't seem like it's a concerted effort to actually reach that group, so right now it's leftist memes for leftists but the potential for puncturing someone's insular bubble Via familiar substrate for the message has interesting potential!