Loyalty points

Very useful for buying extras in the game, most notably dog bones, fertilizer, humus, feed and expansion materials. There is also an upgradeable decoration - the Wellspring of Charity, that can only be bought and upgraded with loyalty points.

Rewards

Every tournament has 6 stage rewards and rewards upon tournament finish. There are also 1 time rewards for reaching a tier.

Experience (Player XP)

Participating in projects tend to increase playing time which helps you level faster.

Purpose

It gives you another reason to jump on and play because you are helping your team out

Belonging

Maslow's third human need - Belonging and love needs - everyone has a basic need for relationships and to be part of something

Esteem

Maslow's forth human need - prestige and feeling of accomplishment - hitting a milestone with your co-op doubles the impact of meeting this need inside the game.

Knowledge

There is a lot of knowledge inside a co-op if you ask. Most people naturally want to help when asked.

Challenge

When you have a few people together working towards a common goal, natural competition pushes you a little. Example would be trying a higher level theme event.

Encouragement

Being surrounded by people who understand the game challenges that can encourage or congratulate you for overcoming obstacles or meeting goals. (Your husband may not understand why you are so happy about catching a Mahi Mahi, but your co-op understands.)

Larger Focus

We all benefit from looking outside ourselves and to the need of others (should I add another goat?)

Relationships

You get to be with a large group of people from different cultures and backgrounds, in different stages of life who are often very much like you. There is also safety in people only knowing what you want them to know. I went 4 months waking up to log on and read good morning from one co-op member. I went scouting and woke up to no good morning; it surprised me.