I dont quite understand your argument. Sprint did exactly what you are saying verizon wouldnt. People who bought the evo 4g still pay $10 even if they dont have wimax. Take your last sentence and replace LTE with wimax and sprint did exactly what you are saying verizon wouldnt. I agree it is stupid, but what exactly makes you think verizon wont do the same. Not that I think they will. I have no idea. Just wondering what makes you think they wont.
It is a completely different dynamic. Sprint did not have anywhere near the depth of 3G Android devices, and they didn't have the IPhone. Further, the Evo enjoyed almost 3 months of 4G exclusivity and even 7 months later they have just the Samsung Epic with the Evo Shift (also by HTC) just now debuting. VZW has 4 LTE handsets coming out late Q1/early Q2 and presumably more in the pipeline.
Also, even with the $10 premium Sprint is still cheaper than VZW despite being the pretty much the only 4G game in town until recently. It's not going to happen on VZW. For starters, you already have 4G on Sprint to compete with and AT&T coming this summer. You simply don't push the mfrs to develop LTE phones and then turn around and price those phones out of 3G markets. And if that were the case, no way HTC scraps the IncHD for the Thunderbolt - you have it supposedly ready to go in Nov but you delay it (quite possibly at the request of VZW) for 3-4 months only to get screwed by VZW?
You can take it a step further. If VZW says "I'll take 1mm LTE Bionics or 2mm 3G Bionics" what would happen? It's simply going to be implicit in that order that the phone is competitive in both markets. VZW is going to be on the hook here and if they price those LTE handsets out of 3G markets they are taking a big risk of eating thousands upon thousands of handsets, and that isn't going to happen.