Updated Calgary, Alberta, Canada
You say you're a returning, non-traditional student but no details so this answer may not be 100% accurate. The reason students are usually advised to participate in college clubs is to add skills and/or experiences to their resumes for when they leave college and enter the working world. Depending on your past experience, this may not be as relevant to you since from the sound of it you already have experience in something outside college. However, you may want to consider the networking opportunities these clubs can offer, and joining the right clubs could give you experience towards your goal after college that you may not already have from your previous life. In summary, under your particular circumstances clubs may not be that important if you are returning to advance an existing career. On the flip side if you are returning to change careers clubs could offer a great way of adding some experience to your studies - you have to consider carefully which to join and what they'd offer your resume after graduation.