I'm not sure you're following what I'm saying. That's probably my fault, for being terse. Even if the negotiating positions are "entirely one-sided" right now, that position leaves the door open for a competitor to capture market share by offering accounts without personal credit attachments. And yet nobody does that. That suggests one of two things: either (i) you can't capture much market share by offering easy terms for a merchant account (unlikely, to my mind) or (ii) you can't stay in business offering those terms.

You can anonymously acquire a Nevada shelf corporation in a week or two. If you were able to just setup a merchant account without a personal guarantee, you could then trivially rack up a significant volume of fraudulent charges without any recourse. (The bank would literally not know who you are)

If you are a real business, you will almost certainly change credit card processors anyway to get better payment terms as your volume increases. The last startup I worked for changed at least three times as our volume grew.