You're making it sound like they force you to go in every single day of the week, with absolutely no benefits whatsoever. You get money while you actively try and find work. If you sign off now, you're still going to be jobless, except now you'll no longer have this money, which can help pay for things like travel expenses when looking for jobs.
You go in for a few hours at most. Let's say you allocate 10am-5pm for job hunting during the week, then the job centre visits are taking out 3-4 hours out of a 35 hour week. That's about 30 hours you still have for job hunting.
If you "can do better without them", why not just take that attitude and use it to do your best to find a job, and in the meantime continue to receive this helpful money? It just sounds like you're using them as an excuse.