Of course I'll try the boots on. But that's not the point. If I walk in without some idea of my prioritized choices on boxing day of all days, I'm going to get run over and not get what I want.
So I need to go straight to what I want (after listing off a couple things) and trying the fit out.
Whether the boot fits me well or not isn't the only point of concern... isn't boot flex & all that important too? I've been told boots like the Burton Hail aren't good for all-mountain riding since they're too park oriented (too flexy), etc, etc.
It is the point. Don't have a preconceived set of notions of what boot you want. You need to try on as many boots as you can. And when they fit, they fit. The 10 boots you "want" may be 10 boots that fit you the absolutely worst. But because they are the boot you want you may fool yourself into thinking they fit well. I know, I've done it. And had to sell pairs I thought fit well.