I use most of those services (except 2 and sort of 5) and don't experience the 'envy' that you associate with them. Perhaps your perspective on them is skewed or perhaps my use-cases are atypical.
I think Linkedin and eBay are stretching it a bit... a very small (though probably real) percentage of use cases for those services revolve around the envy emotions you describe.
>Gmail (before open access) - envy my domain name for my email address
The others OK, but that's a little far fetched. Who gave a flying fuck if you had an early access Gmail account? Geeks? And I don't think it was some kind of envy generating strategy -- just the usual practice of an "invite only" beta.
1. Instagram - completely based around lifestyle envy and like count.
2. Pinterest - envy my "good" taste
3. Facebook - envy my life and my baby
4. Twitter - envy my wit and follower count
5. Linked.in - envy my job and connection count
6. Gmail (before open access) - envy my domain name for my email address.
7. eBay - Envy my sellers badges and review ranking
I think social networking in particular has a strong correlation to using envy as being a "dark" social pattern exploited for growth and stickiness.