This statement is made on behalf of the TUG Board of Directors.
The entity that is an institutional member of TUG is the private company
StackExchange. An institutional membership allows for up to eight
delegates from the institution to benefit from the same advantages as
individual TUG members. StackExchange has chosen to leave to the
community the decision of which eight people receive this benefit; but
this is very different from everyone who registers on TeX.SX
automatically becoming a de facto TUG member.
As for site-wide electronic access, it was never contemplated that
this would extend to every individual who creates a free/automated
account, when an institutional member supports such accounts. As has
already been pointed out, that would be tantamount to eliminating all
TUG member-only benefits, since anyone can create a TeX.SX account.
While we are here, we would like to express our appreciation to
StackExchange, and to all our institutional and individual members, for
their generous support of TUG and TeX.