looks good - they should give them out at concerts, sell them or rent them. Why isn't anyone selling them at concerts anyway? The cost of goods at scale (millions of pairs per year) must be miniscule, it's basically free money that could be shared with concert venues and has no downsides of any kind whatsoever.
why aren't these being sold at concerts? (vending machines etc)?
I guess people just don't care. (not enough 'demand').
I wear these at concerts: https://www.amazon.com/Eargasm-Fidelity-Earplugs-Musicians-M.... A fairly flat 12 dB drop across the whole spectrum. Everything sounds normal, just not excessively loud.