Do pepper plant leaves have burgundy undersides?

This is my first year growing peppers. And in the spot where I planted them I have a few plants that have 2 green leaves, and then I have several plants that look like the green ones except the leaves have a burgundy tone on the underside and a burgundy-ish stem. Are those just weeds? (I know they aren't beets because I have beets growing in a different spot and they don't look like those)