Why do so many people have turkey at Christmas? Because it's traditional. There are plenty of alternatives, but no, it has to be turkey because turkey's traditional.
Why do brides invariably wear white? Because it's traditional. You could wear something green or blue or red but that wouldn't be traditional.
Why are so many boys circumcised? Because it's traditional. You can produce good reasons for not doing it, but you'll probably be ignored because tradition wins out.
If falling back on "tradition" really means that you're too timid to make your own choices and so you just follow the herd, then that's rather sad. But if you really love turkey, and you really love white bridal dresses, and you really think circumcision is beneficial, fair enough, go ahead.
Of course many traditions are to be applauded - like democracy and free health care and public transport and politeness and donating to charities and teetotallers. Something that goes back centuries can be pointless and irrational and toxic, but it may also be a valuable contribution to our daily lives.
Some traditions are so absurdly over the top I can only look on in disbelief as they take place. Like the state opening of parliament, with the Queen trundling along in her golden coach and all the uniformed flunkeys who preside over the various opening rituals. The state opening costs around £214,000.
PS: I was circumcised, but I never found out why. My parents weren't Jewish. It's something I could have asked my father, if we hadn't been estranged for 20 years.