Like it or not, the army was one of the few social services available in Britain during the Napoleonic period for unemployed males and hard as military life was, it was better than what awaited many young men in civil life. And difficult as life in the ranks was, there was an opportunity to better oneself by achieving promotion and, hopefully, at the end of one's service a civil appointment as a barrack master or ordnance store clerk.
Also, despite the prevailing myth that British officers were aristocrats who purchased their rank, a surprising number of soldiers were commissioned from the ranks. Usually they did not reach high rank (an exceptional few did) but they improved their social status and opportunities for advancement.
Volunteering from the militia into the regular army brought many literate men into the ranks and the result is a more substantial literature of enlisted men's memoirs. The Private Thomas Jeremiah, whose account of Waterloo, has been discussed on this Forum recently, was one of 12 children of a tenant farmer in Wales but he could still read and write.
Methodism was a growing faith during the period in both the RN and the army. It was regarded with some suspicion by many officer but it was noted that Methodist soldiers and sailors were more sober and better behaved than their non-Methodist counterparts so it was tolerated.
Sometimes, however, it could be taken too far. In the archives of the United Church in Toronto, there is a memoir by the Reverend George Ferguson, one of the early Methodist preachers in early 19th century Canada. Ferguson started off as a private in the 100th Foot and saw some action during the War of 1812 but stated at one point that he only fired his musket once in battle and sure that he did not hit anybody. Better he had served in the US Army.
DE Graves