A word for something between a "Job" and "Hobby"

Solution 1:

sideline

Oxford dictionaries

An activity done in addition to one’s main job, especially to earn extra income:

Merriam-Webster

Simple Definition : a job that is done in addition to your main job

Full Definition : 2. b : a business or activity pursued in addition to one's regular occupation

Solution 2:

The closest I can get is a sinecure.

A position requiring little or no work but giving the holder status or financial benefit:
political sinecures for the supporters of ministers

Reference:
http://www.oxforddictionaries.com/definition/english/sinecure

Solution 3:

I recommend gig or moonlighting (only works when you have a primary job, too).

It is worth noting that there are other ways English tends to resolve this distinction: we will tack on an adjective and say "well his position as secretary is largely perfunctory in any case," or "it's very much a cush, part-time position." Alternatively, sometimes people will attempt to distinguish between a career and a job, although I think this is mostly connotated and not denotated.

Solution 4:

Tongue in cheek, but the word you're seeking may be the following neologism:

jobby: an endeavor between a job and a hobby

This is how new words come into being, right? It also lines up with your multiple use of "jobs".

Otherwise, I'm not sure there's a satisfactory one-word answer to your question. While not all jobs are created equal by any means, a job is a job: a regular remunerative position [M-W].

Addendum: As pyobum has pointed out, Wictionary provides several meanings of jobbie (or jobby), one of which is actually relevant:

jobbie (or jobby): (Britain, informal) a job, normally a task rather than a form of employment for which one is paid

So, a jobby is not a job as defined by M-W (see above), but at the same time it bears no obvious relationship to hobby.