The SCA has many traditions. Some are as simple as reverancing (bowing/curtseying) when you pass in front of the thrones (whether or not they are occupied), others are a little more complex. In the West, and now Lochac (as a scion of the West) it is often said that Laws can be changed, but tradition is immutable. Even so, some traditions drift out of favour, and new ones emerge all the time.
Some things should be thought of as fads not traditions (even if something lasts a few years it may just be a passing thing).