I already got a job. I don't need one where I don't get paid, and any hobby with obligation IS a job.
This part in particular caught my attention because it is a simple yet profound insight. I've also had this conversation using the same job comparison many times. It is very accurate. BJJ on a team is like a part time job where you pay money instead of getting paid.
However, every team sport is like this. One of my friends plays in a recreational soccer league. It costs money every season (renting the facilities, league administration, paying the refs at the games, etc.). It also involves an obligation. When you join the team, you are making the commitment to attend practice, go to games, and just basically be a part of the team.
If someone doesn't want an obligation or does not take it seriously, that person will be removed from the team. It hurts everyone to allow that person to remain.
Now BJJ can be approached with a team mentality or an individual mentality. However, all of the top places to train BJJ approach it with a team mentality. After having done it both ways, it is pretty clear to me why.
When it is approached with an individual mentality, the training environment sucks. Guys show up when they want and if they want. This carries over to the training. When the instructor wants something to be drilled, guys who don't feel like it halfass it or just sit out. Usually this discourages drilling and hard work, and it eventually disappears altogether. The class becomes showing 2-3 random moves (usually something trendy like berimbolo or the 50/50 armbar or whatever else is on YouTube that week) and then lazy rolling/sitting out/fooling around/talking about girls for the rest.
When it is approached with a team mentality, guys work hard and drill hard because it is expected. People aren't allowed to just do whatever they want because that is not in the best interest of the team. If the team is drilling some fundamental body mechanic like breaking posture in closed guard, you can't be off in the corner messing around with upside down ass cobra guard with your buddy. If the team is helping some guys prepare for a major competition, you need to be there to give them the hard training that they need. If that doesn't interest you, you will be asked to leave the team because you are dragging down everyone else.
My gym runs things like a team. If you want to be a hardcore competitor and train 10x a week, make that commitment and we will commit back to you 100%. We will fly to comps with you to coach you, provide you the training you need, etc. If you are a middle age dad who wants to lose weight and train 1x a week, make that commitment and we will still commit back to you 100%. We will keep you motivated and progressing so that you meet your goal. It is not just for competitors -- everyone is a part of the team helping everyone else.
If you have some special circumstances where you need to commit several places, perhaps that could work if things lined up right. But that is a lot more work, and the benefits don't usually pay off. I can't think of any top guys right now who are splitting training 50/50 between multiple teams. Visiting and paying respects is one thing, but the splitting of regular training is another. They might be out there, but it is certainly the exception rather than the rule.
When there's doubt, most people should default to the rule and stick with one main team. It is important and should be encouraged to branch out and broaden your horizons, but you still need to have that main team for all of your core training.