Cable companies spend $17 billion a year on CapEx, and telecom services, excluding wireless, spend another $46 billion more. http://pages.stern.nyu.edu/~adamodar/New_Home_Page/datafile/.... That's a lot of money for companies that are just resting on the publicly subsidized networks they built in the 1980s... Snark aside, most of the modern hybrid fiber-coax network that cable companies actually use today were built after deregulation in the 1990's. And it continues to be upgraded, which is where that massive CapEx comes in.
Utility (general), which I believe ~ electric co's, spends $31 billion. Absolute numbers don't tell you anything; maintaining even a completely static infrastructure costs something.
You said "what little infrastructure investment they do make" which is directly contradicted by the enormous infrastructure investments they make. Also, electric companies are in the middle of a huge push to replace aging coal plants with gas and renewables. There is a ton of value being added in that sector right now.
I was going to ask what revenue they were bringing in with that CapEx. Am I right in thinking this means they're bringin in $34,000 million from sales and spending only $17 million on infrastructure. That doesn't look like "a lot of money" in relative terms - I must be misreading those figures?