Because being the party medic is not usually a role that captures the imagination.
Hey Im not telling people how to make up characters but its like anything thats had a bit of imagination done to it can turn out to be enjoyable.
Clerics and Druids make great second rank fighters up next to or flanking with the main melee players, thumping away or shooting arrows. Soon as one of your tanks takes a lot of damage, step back combat cast a healing spell, continue bashing away.
Either as a single-spec cleric or multiclass for versitility there is a lot of fun to be had simply being 'the bloke who stopped the party dying' and anyone with 2 brain cells to rub together soon realises that it isnt much fun for everyone else re-rolling new characters or eating dirt when a cure wounds wasnt there.
A healing class is still a core member of any group in my opinion and the mentality of perceived as being 'dull' is their own problem. Play as a team, its why theres different classes in the first place, anyone using a cure-wounds wand to prop up a party because they havent worked out how to make a group is just asking for problems later on.
Why should PC's get a free wand of curing at low levels? Should they get a stronger item later on that lets them do a full heal, simply beacuse they all want to be the frontline hero?
You can do a lot with 3E characters, much more than you could with 2E so theres no excuse for being lazy with imagination and never an excuse for poor play and self-centered characters unless youre running a primarily Neutral or Evil game.
Dont cut anyone any slack if theyre being slack in the first place.