Irrespective of if the author was correct in his use of the service, how is not replying for days prompt and how is tersely worded e-mails informative and professional? The whole thing reminded me of PayPal.
What do you mean? Re-reading the post, Square always responded by the next business day. There was no "days" wait here. The only confusion was the OP tried to make it sound worse by saying "over 24 hours", but all that means is Square emailed him in the morning on one day, and on the afternoon on the next day.
This part is also weird. He received a reply dated April 20th. He then says "the next morning" he received another email about the withdrawn funds, and he replied. Except his reply is dated the 24th. I have no idea what to think about this. Deliberate misrepresentation of facts?
A bit later on we do finally see a multi-day gap in Square's responses, where he emailed them on the 25th and Square replied on the 30th. However, Jason's email didn't actually contain any questions or actionable statements, only complaints and accusations of "thinly veiled threats". So I don't see the response gap here as being significant.
This guy doesn't know how electronic payments work, and has clearly never had to deal with managing a merchant account before.