OK, if she'd gone the e-publishing route, she wouldn't have had the same grumbles. But there would have been others. Different formats, the threat of piracy and Amazon pricing glitches for example. All of which have time implications, and that's before the big time-suck is included: marketing.
If you are conventionally published then I agree that they are asking authors to do more of their own publicity - too much, with too little support IMO. But you'll still have a publicist who will be dealing with the more conventional outlets such as reviews in magazines etc as well as promoting you on-line. You'll also have a team who will deal with all the other stuff involved with publishing, from editing to production to admin.
Now, basic maths tells me that 70% is more than 10%. But your 70% may have to fund some areas that you weren't expecting, whether directly (in the form of hard cash) or in terms of time spent. It's like thinking an advance of £20,000 is a fortune, when - if it's taken you a full time year or more to write the book - it's less than the national average wage, and even less when the agent's commission is taken out.
This isn't an anti e-publishing post, just Caveat Emptor. If something looks to be too good to be true - you get to keep 70%!!! - then it usually is.