Thinking about this a little - what's the difference between a wedding ring and toasting or clincking glasses? I submit that the difference is one of separation from society - failure to wear a wedding ring wouldn't be that noticeable to most and wouldn't really cause you to feel like an outsider in the world. In fact it may draw a little extra attention from those that think you're single. This is to be avoided, so wedding rings are considered good.
Toasting, on the other hand, is something that most in the group won't notice that you don't do if you're out with normal people. But you notice. You see them do it and you know you can't join it. You're intensely aware that you are not like these people. They are different. You don't fit in. Even if you're not happy as a JW, you have no where else to go because you don't belong with these people either.
You can pretty easily go through the list of things they reject on account of pagan origins and the ones they don't in spite of their pagan origins and this holds true for pretty much all of them. If it's something that would go pretty unnoticed either way it's OK to do, but if not doing something makes you feel like an outsider, you can't do it.