It would be very, very beneficial to have 3 tenants for even just the implementation phase so the implementation can go smooth and we can set-up a test environment/UAT along with the Production Environment and the demo environment. If they need an extra tenant for an additional company, then we add that extra tenant as a paid one.
I agree, this takes away a major factor in the decision process. Many of our customers buy Acumatica alone for the extra tenants...