They did that for a while, but Google implemented a policy that what gets shown to the Googlebot has to be the same as what a user would actually see. EE got delisted from Google for violating that policy, and ever since then, they have the answer way at the bottom of the page no matter what.
Click through to this recently answered question from Google's search results[1] and scroll down to see the answer. Then open the resulting link[2] in an incognito tab and poof no answer
That had been Google's policy for some time, they just started enforcing it for a while. IIRC it was around the same time BMW and a couple of other big names were temporarily de-listed for keyword stuffing and similar shenanigans.
