[chc]

Seems to me it's nothing but an assumption on your part that they do profit from these transactions. The comments on the OP suggest otherwise.

You'll see two opposite complaints about payment processors:

1. They let fraud run rampant.

2. They're too hasty to lock accounts.

In order to have less of one, you have to have more of the other.

As for why customer service is so sketchy: Google's customer service is infamously bad across the board. It's not specific to Checkout.