I'll go back to my example of Batman and Harry Potter.
When these two franchises were at their zenith you couldn't escape the fever of these movies. I would regularly see people dressed as wizards and people dressed as batman or wearing garb with these franchises on them.
I've never seen a fast and furious shirt.
I think perhaps you're looking for signs of influence in the wrong place. Capes and Wands are trademark characteristics of wizards and superheroes. And people don't wear them to support the brand
, they're wearing them to role-play. They can't just wear a t'shirt that says Harry Potter. All that is is a person declaring themselves a fan. People that wear capes and carry wands are saying more than that, they're saying I wish I was a wizard too.
Similarly you shouldn't measure F&F's influence by T-shirts. You can measure it's popularity
that way perhaps... see how many people are declaring themselves fans, but we're talking about influence. And T-Shirts are not what defines the characters in F&F. The characters are defined by what? By their cars. And thus that is where you see the influence of the series. In people's cars.
And after the first F&F what did every 16 year old boy go out and buy for the aging Civic?
Or at least they tried to. And if they could afford it they probably detonated their engine shortly after and couldn't afford another one. For everyone else too broke to buy a NOS kit, and with too much dignity to just spray paint a 2L coke bottle blue and put a NOS sticker on it, what did they do?
They settled for a fart pipe and a park bench.
The homemade Cape and Wand equivalent of the F&F series. And I think by that measure the series has been unbelievably influential.