The threshold would logically be somewhere around the <insert support cost here> mark. This might be 0 or millions of dollars a month. But expecting it to be included and complaining about it when you're purchasing goods for less than a support engineer costs an hour I'd say you should not feel entitled.
Raise the bar of communication a bit please, it's a market with many players, if you don't like the services from Google you take your business elsewhere instead of complaining about unreasonable expectations.
You're entitled to it, but I think you're trying to justify a really horrendous conclusion that a business shouldn't reasonably be expected to provide some form of human customer service in some fashion or another if it detracts from their profit margin.
And you're looking at this problem in a weird way IMO. You're worried about the costs of support costing Google too much and examining the costs of 1 support engineer against 1 customer, when the real equation is that 1 support engineer should be enough to service the needs of a great deal of customers. It's not 1 support engineer for 1 customer paying $30. The equation is 1 support engineer that can service the needs of a great deal of customers paying $30 each.
Raise the bar of communication a bit please, it's a market with many players, if you don't like the services from Google you take your business elsewhere instead of complaining about unreasonable expectations.