An indicator is not definitive proof.
Of course it's not. I fully agree.
In the normal context one can safely assume that it is.
Of course you could present examples out of context and different conclusions would be reached, as in ihavenojob's examples. In which case the context determines the assumption.
Someone with a crash helmet at a Motor racing event can safely be assumed to be a driver. Someone on a stage with a dog collar can safely be assumed to be an actor. All very simple and reasonable.
Someone at a political rally wearing a white hood can safely be assumed to be representing the KKK.
A majority of participants in these discussions, assumed that someone wearing a dog collar, on TV, was a vicar of some sort.
your claim which you failed to back up with evidence.
The evidence was there for all to see.
But you corrected me and I accepted your correction. The person on the march was wearing a replica of a helmet as worn in the middle ages or by the crusaders. Both fundamentally racist. Therefore one can safely assume that they sympathise with the ideology of the crusaders or medieval soldiers.
I could say you're a terrorist sympathiser because you wear shoes.
You could if you want, but it would be extremely ridiculous. I didn't make any claim because the person was wearing a hat! It was the type of hat that suggest where their sympathies lie.
If you suggested that my type of footwear suggested some characteristic you might be more realistic, e.g. blue suede shoes, waders, riding boots, long leather boots, etc.
In other words, you're full of shi.t and you try really hard to deflect from the fact everyone can see it.
If you can't debate without recourse to insults, it says more about you and your flimsy argument than it does about me.