Well, I am perfectly qualified to answer this question:
There are some perks, however, you've got lots of free time with nothing to do - so if you're interested in expanding your mind a bit you can do lots of reading...and on virtually every subject available in the leisure library.
Jails always have a law library too, but I'd not bother with that - there is no law in the USA now except for B.H.Obama, who Eric Holder says embodies the Constitution....
You learn food appreciation skills in jail - and amazing ways in which you can make Ramen noodles very appreciable.
You learn drug appreciation in jail - no, nobody yet has figured out how to keep illegal drugs out of jails, and especially because....(just like in the non jail world) - it is typically the authorities that sell them.
....but if you are poor and in jail, you'll be all over that instant coffee like it was crack cocaine.