I cannot give you the reasoning behind why the builder structures things in the way they do.
I read the contracts, then ask questions, like what if we do this or what if we do that. Then I sit down and explain it to my clients AWAY FROM THE SALESPERSON. Then we go together and talk to the salesperson. In general the salespeople are not thrilled with my presence. In all cases the answer from the salesperson is we keep the earnest money. Now I “would say” that if there was a tragic situation, or perhaps job loss, or something that you would show them to be an extenuating circumstance that is out of your control, then you most likely could get them to refund you the earnest money.