Plus deeply discharging a lead acid battery shortens its useful life. Just like Li-ion calls there are a certain finite number of full cycles that a lead acid battery can provide. The deeper the discharge the fewer the cycles. Automotive batteries are not meant to be deep discharged. Golf cart batteries can be discharged more deeply; they have more lead in the plates. And batteries designed for off grid power use have even thicker lead plates, and can last through many more cycles.
Here’s a good FAQ on lead acid batteries, aimed at the off grid alternative power crowd.