This is a logical fallacy called false presumption. The most segregated hour in the week is possibly the church hour; other than that, segregation is not a cultural possibility in the USA. The segregation of church is voluntary.
Because in prison, they have to separate the monsters for security reasons. The correctional officers are in too much danger and underpaid as well. That's where segregation exists and has nothing to do with race. People like you like to keep racism going by asking stupid questions like you just did. Stop the madness.