It doesn't make sense for a company that's trying to sell itself to also start making large cuts - it may drive your own price down by signaling that your businesses lack potential. The acquiring company will calculate in the cost (and savings) from the cuts ("synergies", to use the banking term) and just roll them into the purchase price.

So if you're the selling CEO / board, you get to claim you sold the company whole, and if you're the buyer, you just blame the cuts on the increased efficiencies to be gained from combining the companies - it's a sign that the deal is "successful" and you're achieving the synergies you modeled before the purchase.