> And if you're not going to spell it out due to your morals...
Nah, this isn't a moral issue.
I'm willing to do free labor for an open-source project (whether or not it's a commercial project), as that labor benefits everyone. I'm unwilling to do free labor on a closed-source project, as that labor only benefits the entity that owns the code. This goes double for a commercial closed-source project, because in that case I don't see a cent of the money that the code owner gets from my labor. [0]
If you think that wanting to get a piece of the fruits of one's labor is a moral issue, you have a very strange relationship with work.
You could bridge the ipp server of cups over webrtc to a native listener that talks to the usb port. Webrtc to localhost might raise some red flags, but could be a neat alternative to the chrome requirement. Use at the very least some hmac key pairing to ensure others can't easily piggyback on the listener. I just saved you a few bucks.
And if you're not going to spell it out due to your morals, don't comment.