Earlier quoted context omitted.
It's a very small cost that all companies should already be able to handle if they're to be trusted with personal data.
It's absolutely not a small cost. It cost the last startup I worked for around two weeks of development time, plus in many cases it prevents us (or adds massive restrictions) on collecting contact information from leads. It has certainly affected the bottom line of companies like Facebook and Google, but they can afford to take the hit, not all startups can. I'm not really disagree that companies "should" do it. But…
It hurts and sets up barriers when you want to collect data which is not needed for fulfilling the purposes of "doing your business".
Nobody keeps you from saving contact information and communicating it in that way. But collecting all kinds of data to build profiles and get on my nerves, because I wanted to test your software is getting more and more complicated. And that's good for (end) users privacy.