Ok, so is there any reason that a spy would have a cover job (legend?) that has absolutely nothing to do with spying? I know that some spies have jobs where they work at the embassy of the country they're in, and then get information back to their home country when it's needed. But is there any reason a spy would have a job that has NOTHING to do with intelligence?
It doesn't have to be ultra-realistic and to-the-letter (the tone of the story is pretty fun and light) but I at least want it to be reasonable, believable, and something that could maaaybe happen in real life. (and it would be best if it is something that actually DOES happen in real life!)

(additionally, if there's anyone who can explain stuff about how spies are recruited to these sort of long-term assignments, where they live away from the home country for a long time and have jobs and lives there, I would really appreciate it.)

thanks!