They’re ordering a batch. They can say “don’t put a wifi chip into it” and it will be cheaper because no money paid to the wifi chip maker.
It don't work that way. On mobile devices, like phones and tablets, they use SOCs (System on a chip) that combine the CPU, GPU, and connectivity.
For example, you can review the specs for the Qualcomm Snapdragon 600 series.
They would have to redesign the entire board.