To avoid letting down your friends, you are obligated to play when you don't want to.
"youre encouraged to join group quests that take place over a week and everyone's steps/flowers planted are totalled together towards the goal"
"Logging in everyday and playing maintains an active clan, which has its perks with events"
"There a guild system. To get points, you'll have to check in everyday and design a room with one or two other members from your team. You have to choose your room and complete it within a few days, and some guild are really competitive and won't hesitate to remove inactive players or players who don't manage to get an A for their design."
"A little bit, but it's not directly encouraged by the game the way e.g. WoW raid guilds can get."
"You can join a club, which will earn rewards for battling a daily club boss. Everyone who battles the boss, if the combined attack is successful, earns rewards."