"they should be able to wear what they want."
Absolutely. They 'can' wear what they like.
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"break an ankle...paramedics, mountain rescue team, ambulance, maybe a helicopter, all to save their dumb ass."
In the world I want: they got thenselves into it, they can get themselves out of it.
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"Not to mention the cost of insurance to cover, and lawyers to defend the trail owner, medics, rescue team and shoe manufacturer from your lawsuits."
In the world I want: financing their healthcare is 'their' business, and the court would dismiss any such case based on 'hiker beware' (your dumb ass is your concern, dumbass).
In the world I want: morons and parasites wouldn't last long.
In the current world: hikers who stumble out unprepared can get others to foot the bill for their ill-preperation.
Yeah, let's keep doin' that...