Only time I tend to use easy mode for a typical playthrough is when I'm playing a game of a genre I can't play very well (which would usually be shooters). Otherwise I'm a typical "normal first" kind of gal and I work up from there. If it's a game, genre, or franchise I know well (like Ratchet and Clank) I'll crank the sucker up to as high as I can or would give myself certain handicaps. For handicaps, as an example I'll say that in all Ratchet and Clank games I've done no armor runs as well as no armor + highest difficulty runs for ones that had difficulty scales (and for those wondering, it gets to the point where nearly everything can kill you in 1-3 shots from tiny scrubs to bosses...so it ain't bloody easy, that's for sure). With armor and any difficulty below hard, the games are pretty tame.
Regarding shooters, yes, certain shooters are challenging for me even in easy mode (I'll want fruit punch for my sippy-cup, please). I save-scummed the hell out of Black Mesa. I'm not used to the control layouts and the lack of mobility (as well as the first person perspective) as I've been playing mostly platformers for the last decade. It was a huge shock that I don't think a lot of people appreciate. I wouldn't have even bothered playing Black Mesa, Spec Ops: The Line, or any of the Bioshocks without an easy mode (ok, Bioshock 1 was pathetically unchallenging on easy, but I was dying so much in normal that I ran out of supplies and couldn't keep up with the enemies without dying a million times. Stopped being fun). Though I did manage to get through The Last Of Us on normal (as the first shooter I played on anything higher than easy). Felt the burn, but very satisfying. Almost tempted to try survivor and see what shenanigans I can get into.