Collective choices get made within capitalism all the time. Corporations, clubs, cooperatives, unions, associations, etc, cities, counties, countries, etc, are all legally established collective choice making groups. There is also nothing preventing people from forming their own groups by free association.

The key feature of a capitalist enterprise is that the workers and the owners are not the same group. This is in contrast with a socialist enterprise, where the owners and the workers are the same group.

There is a ton of stuff preventing people from forming their own groups. Have you seen how companies (see Amazon & Starbucks recently) react to people attempting to do so?