It was actually the coin mech issue, and that really wasn't the issue. The issue was Rick's total lack of transparency and his blowing off of legitimate questions about an issue he caused and insisted his research said wasn't a big deal.
If the game had been announced without coin mechs, it would have blown over quickly. But when you take them off the game after deposits became non-refundable, claiming it would only be an issue for a few, refuse to back that up and ignore the logical question of "if so few are impacted, why not just send mechs to those customers?", people began to see he wasn't as straight forward as he seemed.
All that "if you have a question, just call" talk was just a ploy to get people to stop asking questions Rick didn't (and still doesn't) want to answer. In hindsight, maybe a good move on his part, because as long as people were focused on the coin mechs, they weren't going to figure out the game was slipping 4-6 months.