While online listening can be anywhere in the world, the vast majority of online listening is to local/area streams versus stations in other areas of the country. You might disagree but that's why you're here. The typical listener tends to be local. To prevent out of market listening, some stations use "geo-fencing" so they don't pay for listeners out of their region. I've asked hundreds of people in the past few years that listen in the office and that listen online with a good 80% or more choosing a local station followed by the personal music library. Less than 1 in 20 listen to distant radio, usually a listener supported station and mostly within the state. When I asked, most say it was the station they listened to driving to work or they wanted to feel 'connected' to the community. (Literally, a jock I used to work with and I decided to ask everyone we came across that we knew worked in an open office if they listened and compare notes...all results from Houston).
The talent fee you are paid is just that. You either agree to the terms or not. If both parties don't agree, there's no deal. No matter what the standard rates are, etc., both parties must agree, so it is less about standard rate and more about both parties being okay with the deal.
I know some national advertisers do regional campaigns but more often than not, it is a national campaign. If you saw an ad on TV on WGN, for example, and were watching via cable TV in Boise, you, as a viewer, would likely understand it might not apply to the Boise market as well (sure some wouldn't have a clue and many of those folks tend not to have a clue about many things). Or the advertiser might have the local ad only air on the over the air TV and the national ad airing via cable. When I was in a small town watching TV stations 150 miles away from me I assumed the price was good only in that city, not locally, feeling I had to drive to that city to get that product at that price.
I doubt many listeners want to hear the commercials online but the lack of only makes monetizing the stream more difficult. I think radio would welcome running commercials even though it might lead to paying more to stream. As my owner once said, it is much easier to spread your money around when you are making it. His point is when you make a dollar pieces of it go somewhere and as long as you make more dollars, the extra portion you shell out is okay because you make more...simply a truism in business.
Yes, VO is a very tough way to make a living and few really can without at least another job to count on. Radio is much the same way. A few rise to the top, some are too stubborn to change careers and stay in the business but most never get past the first few years before doing something else. Many career paths are that way but what seems to make VO work so difficult is it seems to be less about ability as much as what they want at that moment which seems to be a bit of an unknown. That makes it scary because you can't really control your career by learning something new or getting more experience like you can in other lines of work.