A:Answer The short answer is no.
Verizon has an exclusive as a "retail" partner from a carrier perspective. Obviously you can get a Pixel at Best Buy which is another retailer but you can add this phone onto any carrier.
Things to consider:
If you buy it from Google, the phone is unlocked and available at full price or through financing. You will get the security and OS updates from Google.
If you buy it from Project Fi, it is also available unlocked despite the Fi sim at full price or through financing. You will get his security and OS updates from Google.
If you buy it Verizon, you can buy it on contract, full price, or through financing. If you buy it from Verizon, Google will handle the monthly security updates but Verizon will handle the larger OS updates "in partnership" with Google. (This sounds like a repeat of the Galaxy Nexus.) But the bootloader is encrypted and the phone is unlockable.