A lot of the feats of strength don't really do anything except show that you're willing to spend money or extraordinarily lucky, or in the right place at the right time, though. Obviously one like the epic pally and warlock quest lines shows you spent time to do that really crazy quest line, but past that?

Rare mounts? All that means is you won the roll on a drop. It could mean you ground for that item for ages, or it could mean you walked in there by yourself or with a group and got it on the first drop. Stuff like the brewfest steins, baby blizzard bears, etc- you were in the right place at the right time, you hardly had to do anything. And finally you have the collector edition pets and pets and mounts from Blizzcon, etc- those mean you were willing to spend money.

Very few feats of strength actually indicate any amount of work. Sure they are "hard" to get- in that not everyone can get them. But most of them you don't get because of hard work.

"I love Feats of Strength because they have the ability to show one's dedication."

Or that you have played longer than anyone else.

I worked for my champion of naaru title, both in doing a very long questline and in downing all the T4 content. I came so goddamn close to getting the hand of ad'al title it still annoys me a little thinking about it (Vashj downed, Kael'thas to P4). So yeah, some feats do show a real achievment by the player that is not the same now, and are therefore no longer attainable. Others are pretty much like you say, but that's the reason they're feats of strength and don't give achievment points.