In a perfect world issues of job/retirement security are supposed to
be resolved by academic tenure which, at least in the US,
traditionally amounts to a quite livable retirement pension as well.
Tenure seems to be an endangered institution, however, and it very
much remains to be seen how these things will shake out in the
coming years.
As for publishing popular works alongside academic ones, this can be
actually be harmful to one's career in some academic fields, insofar
as it's sometimes looked down upon.
- N