At first glance a class is a class, but as an instructor I'll let you in on a dirty little secret. Most instructors treat them differently. The venues have different goals and the nature of the students isn't the same.
At its core, clubs are social scenes with food and drinks, not universities or learning centers. If you learn there, great, that's a bonus, but it's a side effect for the club owner. The goal of the club class is to pack in bodies who buy drinks (and/or food) and return regularly.
At the club, drink/food numbers rule, and the club owner isn't directly worried about the quality of the instruction, as long as the numbers hold up over time. A popular instructor trumps a great instructor, and making it fun and accessible is the mission. Club instructors often simplify their materials and don't worry about the details, knowing slowing down the class isn't workable for most students.
Some clubs have excellent instructors and there are some quality club classes, but that isn't their mission.
At most studios, the focus is on dancing and fitness, although they do share the "getting people to return" goals of a club. The difference is the focus. The studio needs you to return for the dancing, the club wants you to return for the food and drinks.
Dance studios tend to have much higher numbers of repeating/returning dancers than most club classes.
Studios often have "series" classes, where it's assumed the students are building on the previous classes, and repeat students are the bread and butter. The instructors know people attracted to this environment are interested in improving their dancing, and generally put up with more foundational work than most club situations. Longer term this creates stronger dancers, so the studio tends to attract others interested in higher level dancing.
Studio instructors often don't "baby" students. They are nice, but most will push you harder and tend to take a much longer term perspective on dancing than the club classes. Foundation building, some conditioning and stretching are often part of the process, and the instructors assume you want to grow your dancing and will practice outside of class.
Both venues have their strengths and weaknesses, but most people start their dance education at the club classes, then grow into studio classes when they get more serious about improvement.
In part II of this article, I'll expand on the differences and my experiences in the two environments.
Let me know what's worked for you.
To know how to criticize is good, but to know how to create is better.