You can't use beeper on a Mac. You need a Mac to trick iMessages.
iMessages is a proprietary system that Apple spent millions of dollars and thousands of manhours to develop. Beeper is trying to cash in on the work that Apple has done without compensating it. That is stealing.
Apple has every right to protect its intellectual and proprietary property. Beeper does not have the right to use it without Apple's permission or compensating Apple.
You can use Beeper on a Mac, it's how Beeper cloud works and one way you can obtain your private token for the app we're currently discussing.
If you have access to a Mac (I don't) and you have an Apple ID (I don't) you have every right to access and use iMessage. If you want to take your completely legitimate authentication token and add it to Beeper mini to use on an Android phone (I don't), then that is completely and totally your business and fine with me. Nobody has been harmed and nothing has been stolen.
Now, with the original beeper mini you may have had a point, and this discussion would be more interesting. But how it works currently they are nothing more than a third party middleman between a user and an account they have completely legitimate access to, not really any different than TeamViewer or Chrome remote desktop...
As I said earlier though, this is a pointless argument because it's about philosophy not technology... We're going in circles with no chance of resolution.