QFT
Generally speaking, you use social media. That’s why those links are there. I also might occasionally text someone.
I don’t interact with any real life people via email. I’d end that with “anymore,” but, really, most people skipped the email phase. I only really used it in college–as it was easier than getting a girl’s phone number.
What’s so difficult about copying and pasting the url into an email, if that’s how you were planning to send a webpage link to someone else? That’s how I sent people url links from day one on the internet. What’s with the buttons and the menu options?
Am I being whooshed or something? 
And for god’s sake, write an actual sentence or two about what you’re linking people so it doesn’t look like a phishing link from a hacked email. I only send links as part of an ongoing conversation or else I wouldn’t have need to send them, anyway.
Also literally the only times I print anything out any more are concert tickets, event/hotel confirmations, postage labels, and papercrafts. I don’t need more papers laying around my house.
Generally, I copy the link and then I post it on their facebook page with a comment about why I thought they’d be interested. If I wouldn’t mind a conversation about it, I do it publicly but if it’s only relevant for the two of us, I do it privately.
I don’t like when my mom uses the “send link in email” button on a site because now my email address is in the email database for that site. I taught her to just copy and paste a link in an email to me.
Sites don’t make money off the sharing widgets. They do often get live tracking out of it, so they know what pages they have are popular. Good to know because shares is a different statistic than hits. Some of those widgets do offer email and track shares via email but seriously, don’t go giving away your friends’ email addresses.
And in turn these data can be turned into better ad sales/pricing, so there is some financial reward at the end of the day.
If I want to preserve a web page (which sometimes is a good idea, as they do not always stick around for ever), I do not print it to paper, instead I ‘print’ it to a PDF file, using Cute PDF Writer, which as a printer to my browser. (‘Cute’ is free, but I believe there are several other free programs that do the same job.) This saves a lot of the precious ink, and the files are easier to store and find again than paper copies would be. If you really need a paper copy later on you can still make one. You can also save web pages as MHT files, a facility that is built into IE, but can be done in Firefox with an extension. I prefer the PDF method, though.
Would it be hard. No, but… the Twitter, Facebook, and Google+ share links are all little widgets generated by the site in question. Dropping them in requires almost no effort. Building an “email this page” button is a little trickier as you have to do it yourself. Pre-made email widgets are available, but they’re as common (and in my opinion, not used as often) as Twitter, Facebook, and Google+ share links.
Chrome does not appear to offer link mailing as a standard feature, but there are extensions available if it’s a feature you require.
As to printing, the other reason for print icons disappearing (other than fewer people printing), is that with CSS @media rules (from CSS2 if I recall right), the browser’s print function can (and should) be used to render the page in a print friendly style automatically – removing navigation elements, background images, etc and paging nicely. (Automatically from the user’s perspective that is, the designer still has to set up the appropriate styles to make the page printer friendly). 
Uh… I do? It’s a bit easier sending a link to a FTP site containing our 24mb Media Kit than it is printing out 5000 of the damn things at $6k, then mailing them for $3-5/each.
What a bizarre question and asinine observation.
E-mail is simpler for me, it is automatically private and I control exactly what people I send it to. I share links with friends/family nearly every day by e-mail.
The (good) web site owners know what links on their sites get used most. And they refine their sites with that info.
Socially, most web sites are accessed via mobile devices now; smart-phones and tablets. They don’t have printers connected to them.
Also, social web users use social media AS their Email. For them, the social-media links equal ‘Email’.
Business wise, things are still PC orientated, but mobile devices are growing strong. Email and printing is VERY much in-use.
There’s also the issue of social media being very dynamic. Once one becomes popular (and businesses adopt it) the target demo., ‘kids’ abandon it. RIP MySpace.
Yeppers. As the date approached when MS would no longer support XP, my office went to thin client rather than pay for upgrading to Windows 7. And I couldn’t help thinking, “haven’t we been here before, back in the time-sharing era?”
I don’t necessarily care how private it is when I share say an article about virology with my mom or a review of a play at a local theater with a friend. I actually don’t mind input from the wider combined audience of our friends.