> There must be something else of monetary value they receive because that's a full time job.

No, its not a full-time job. New Hampshire is among the (many) states without a full-time legislature, though their pay is pretty low even by the standard of part-time legislatures. [1]

[1] Not particularly current, but this doesn't change all that much: http://www.ncsl.org/research/about-state-legislatures/full-a...