Two separate things, priced separately: your own cards, and a community you run. (A group is a quick free list you keep; a community has its own members, lists and organizers.) Most people only ever need the free plans.
Your cards and your contacts. Paid by you.
Groups are free on every plan: one list of up to 50 people you can text or email at once.
Clubs, leagues, HOAs, companies. Paid by the community's owner or its billing admin (say, the treasurer).