It doesn’t. However, if you want to have a professional and trustworthy appearance it should. If you’ve ever shopped online, you’ve experienced the hesitation when you click purchase and the credit card entry form looks different from the rest of the site. A little consistency goes a long way.
The long-term goal is to provide a “Bring your own Heroku” of sorts, supporting many platforms. While PaaS is nothing new, the serverless ecosystem is making this kind of program increasingly trivial, however AWS and others often suffer in terms of UX due to the flexibility they provide. Up aims to abstract platform internals away and provide a user-friendly solution.