Everyone i ever talked to says that realm 667 stuff is pathetic. Meaning when someone uses it in there wad its not good then? My main question here is do people use anything from this site at all?

Most projects either try to make their own resources, or try to be Boom- or Vanilla-compatible, unfortunately. There are several quality mods that do use R667 resources, though.

However, a lot of people think of R667 as a "build your own mod" sort of thing, and have a bias against using its resources. I don't see the logic in that argument, because using only Vanilla resources is much the same; you're not adding anything new, just using stuff already made.

Which ironically, is far from the entire point of ZDoom in the first place. There is a reason for the creation of DECORATE, Randy And Graf Zahl didn't put their efforts into it to have people complain about it.

Besides, what with all the Quake features (such as the console), do people honestly expect that the appearance of new monsters, items, weapons, etc. wouldn't come?

A lot of the hate either comes from designated haters or by those who've only played mods that don't use the resources well. There really shouldn't be any worry for an author of a good project using a good R667 resource. If they fit well, then it will be liked by those who matter.

It simply depends on the way you use it I guess

Is ROC a good use of realm667 stuff?

I think thats the only thing i could think of. I personally love the wads here, i think they're are some pretty cool stuff here that takes time and skittles to do. I'd/will use these wads if any up coming wads i plan on making.

In my case, i use monsters from the bestiary just for fun, but i have to admit that i don't really use all monsters, i am currently using about 20 monsters and maybe 4 weapons.

But i think this is very good, for the people that makes maps and stuff, it makes that the game doesn't get boring if you play it a lot.

Let's be real, if we only fights against cyberdemons, zombies, imp's, etc.
People will mostly get tired of the game and leave it and maybe play it a couple times a year.

I wouldn't say that. Look at Hell Revealed, Alien Vendetta, Scythe, and the other popular megawads that only use vanilla resources.

Quite a few of those megawads actually use custom textures if that counts.

But those megawads are popular because they have very good level design, the fact that they use vanilla resources really has no impact or relevance to their ratings.