No, not at all!
On the other hand, we have to do something, to greet each other somehow, read some words, dress some way. Why not do such things? As I often say, for example, we have to do something with our hands when practicing 'walking Zazen' (Kinhin) ... why not hold them in the traditional manner of Shashu (I mean, better than sticking 'em in your pockets)?
As well, there are parts of our practice which we do BECAUSE we resist (for example, when visiting a temple for Retreat, I usually put my heart fully into ceremonies and arcane rituals BECAUSE I resist and think some of it silly or old fashioned). Ask yourself where that kind of resistance is to be found (here's a clue, and it is right behind your own eyes).
What is more, there is method to the madness, and many (not all) customs have centuries of time tested benefits ... embody subtle perspectives ... that support and nurture Zazen Practice at the core. Many parts of our Practice, though "exotic", are worth keeping, even if they strike someone as strange at first. Bowing, statues, rigid decorum in the Zen Hall and, yes, weird talks about Koans all fit in that category. They may seem like unnecessary "Japanese" or "Esoteric" elements at first, until you understand the role they serve. I have given talks on all these things recently, for example ...
http://blog.beliefnet.com/treeleafzen/2 ... eat-3.html
On the other hand again, it is okay to abandon or reject many practices. However, KNOW very well what you are rejecting before you reject it. Absorb what is useful and discard the rest. For example, I think Oryoki [formal meal ritual] is another example of a great practice, and worth keeping..
Some things I keep out of respect for TRADITION [the robes, the ways of doing some ceremonies]. It is important to keep ties to where we come from and to respect our 'roots'. Some things also have a special symbolic meaning if you look into them, so worth keeping [for example, a Rakusu]
But other stuff, no need to keep: For example, I usually avoid to chant in Japanese or Chinese [except once in awhile, out of respect for tradition]. Tatami mats and Paper screens have nothing to do with Zen practice particularly [but I happen to live in an old Japanese building, so ... well, tatami and paper screens!} Some things I think are just dumb (except symbolically), like the Kyosaku stick. Incense is great, until it was recently shown to cause cancer. Many beliefs of Buddhism are rather superstitious things that were picked up here and there. I abandon many of those.
The outer wrap of Zen Buddhism is changing greatly as it moves West. The greater emphasis on lay practice over monastics, the greater democracy in what was a feudal institution (arising in societies where the teacher's word was law ... oh, those were the days! ), giving the boot to a lot of magico-supersticio hocus-pocus bunkum, the equal place of women ... heck, the use of the internet to bring teachings that were once the preserve of an elite few into everyone's living room.Those are good and great changes to the outer wrapping (you can read about them in books like this one (author interview here: http://atheism.about.com/library/books/ ... anChat.htm ). The coreless core, however, remains unchanged.
Do not throw out the baby with the bath water. Many completely "Japanese" or other exotic practices which seem silly at first are worth keeping. ...
... other things, like some of the arcane incense, bell & drum filled rituals, take them or leave them.
Gassho (an Asian custom of "Pressed Palms"), Jundo (a Dharma name)