I'm one of those user's that buys a phone with intention of rooting it from day one.
I've been stung in the past by manufacturer's (HTC) who dropped support for their devices leaving certain standard features broken because of their own crappy software. IE the HTC one X+ a 64gb quad core tegra 3 phone with HTC's own software had a bugged bluetooth stack (AOSP worked fine). The device is perfectly service able and fine but because of flawed software has issues and security flaws that were unpatched. Rooting allowed me to have the device work correctly on patched roms.
I now have the Nexus 6 but my old HTC still works perfectly for a family member and its rooted.
I certainly feel no need to use my phone to pay for things, I will just use my card for that. But I certainly will not stop rooting, the device I can't root is one I will buy.