There are exceedingly few people who have actually been banned here. Of all of the accounts that were banned, most were accounts created by spam bots. There is notably one member who was banned who was very active and had an enormous post count. But, that member actually had five accounts. This was one of the many reasons he was banned, because he was using his various screen names to publicly flame people and then use his other aliases to back himself up.
So, fear not. It is very rare, and we only ban a member upon very careful consideration and as a last resort... Or when we determine that an account is was created solely to spam advertisements.