[lrm242]

It makes a ton of sense, actually. Intense fear drove large demands for liquidity thus spiking volatility. Thinly traded stocks and ETFs were hit harder than thick ones. ETFs, in particular, had additional demands placed on them as their underlyings were thrashed about at the open as many rushed to sell. The halts were from both limit up/down price band violations and volatility pauses and they did exactly what they were designed to do. In short: liquidity costs money and it isn't an infinite resource.