Salary positions should be give and take on this.
You sometimes have to work more than 8 hours a day to get the work done and in return you get to work less than 8 hours on days that the work gets done faster or there is less work to do.
Having a discussion like this would only work where the workforce was in a seller's market. That exists for some skill sets, in some places (like the Bay Area). But in most parts of the world, it is most definitely a buyer's market. When it's a buyer's market where the buyer has fixed resources, the seller must make concessions in order to stay in business.
That's a fair point. Although it makes me think how do freelancers still manage to find clients all over the country. While it still can be a buyers market I guess you end up with freelancers making lower wages but with more clients.