That wont be far off with South North when you look at the make up of the side a lot of the players are very successful away from cricket, partners at law firms etc and have turned down the chance to play cricket at a higher level as a consequence of this. Given they dont need the extra pocket money they'd rather play in a successful side with the opportunities to play in National Finals / win leagues. Well run club worth millions (accounts are published online) and the right people round them who can invest it - its a business as opposed to a local cricket club and in reality its very difficult to compete with them. However that doesnt mean you cant try ! Newcastle pushed them last season, Stockton won it the year before and Chester are generally there or there abouts.
In terms of money paid out I suspect division one pays out more than the top league, you see a lot less movement of players between clubs in the top division, to a lot of players the money is secondary to the enjoyment they get out of testing themselves at the highest level they can play at. Very few players jump ship for an extra £300 a season, a lot of players get offers of a couple of grand to play in lower leagues but would rather play for nothing or a lot less in the top league.
I always thought it was the other way round in local cricket up here, players would rather earn more playing a lower standard than earn less playing at a higher one.