They don’t mate much— and therefore have no “increase” despite exhortations in the Bible to “go forth, be fruitful and multiply”.
Shakers are so “gifted with simplicity”... they forget sex, or tabooed it.
Shaker prayer meeting chant:
“Shake, shake, shake along, Daniel,
“Shake out of me all things carnal.
No fun in that, IMO.