I fully agree and the sad part is everyone that's "pre-ordering" think they will be guaranteed to get a phone on release day. There were a lot of people who pre-ordered through BB and RS that got the shaft last year when the evo came out and ended up not getting their phone until july. The only thing a pre-order guarantees is that you will be parting ways with your $50 with nothing else to show for it. You are better off just walking in to any sprint store that day and picking it up.
Edit: Like my grandmother use to tell me when I was a little boy "A promise is a comfort to a fool"
Actually, when you pre-order you aren't guaranteed to get it first thing it's released. You are guaranteed to receive the device based on your position on the pre-order list, based on stock. So if they only get 2 phones and you're #3, you're going to have to wait until their next shipment. Note that larger stores that do more sales volume in mobile sales will likely get more devices then a smaller store. Pretty much every store will get 1 device likely, meaning if you're #1 then they reserve the first device they get in stock for you to pickup.
And the $50 is a gift card you get from BB, which can always be returned for a full refund. At the end of the day, if you end up being able to get it faster somewhere else you can always do that then get a refund on your pre-order at BB.
Plus, your assumption that you can simply walk into a Sprint store on opening day and waltz out with an Evo3D like that seems overly simplistic rather then realistic. In all actuality, there will be people obsessed with this phone that will be waiting in droves outside the store before it even opens, and if you've ever bought anything in a Sprint store I'm sure you know that it takes them forever to get through even 4 transactions. Since they appear to be taking pre-orders now as well, those customers will get their devices sooner then people off the street who walk in.
I think regardless where you want to get your phone from, it all is going to hinge on supply & demand. If Sprint/HTC underestimate demand for this device and the supply is limited, you'll be lucky to get one on opening day no matter whether you pre-ordered it or not. All indications are however, that since pre-ordering means they reserve a phone for you, then anyone off the street won't be able to get one until AFTER all pre-order customers have their devices first. This would go for Sprint stores (since they also appear to be taking pre-orders) as well as BB.