I'd say heatspreaders help, but it's not like going from stock cooling -> tower cooler on a CPU kind of transition. Yeah, most people who don't do anything with a computer other than everyday work can likely get away with bare RAM. At the same time, your basic heatspreader usually doesn't add that much to the price, the higher-rated RAM just tends to have more ornate/efficient spreaders to dispel heat from the higher speeds. Fan on memory is the farthest thing from necessary unless you're trying to max out the memory speed for some reason...with DDR3 there are insane 2000+ ratings, but there aren't really any benefits going beyond 1600MHz.
Hehe.... Yeah, heat speaders on RAM are mostly Bling. Peeps even order RAM, MB's
PSU's by color. Some guy wanted to paint his CPU heat sink and then there are the fans, gotta' have the proper LED color.