Guh! No. I'm the opposite. Rituals, by their very nature, should be open to anyone REGARDLESS of having a feat or not.
Without going into technical details about whether it's a feat or a background or theme or whatever, I agree. I think rituals offer a fantastic, evocative way of opening up mystical or magical effects to non casters, while providing effective constraints to differentiate from the trained magic users and clergy.
It doesn't need to be glowing runes on the floor and wierd ingredients - I think of Rambo repetitively, compulsively sharpening his knife as a kind of ritual. Theoden strapping on his armour at Helm's Deep as a ritual.
In the Iliad there's a motif: 'War - I know it well, and the butchery of men. Well I know, shift the left, shift to the right, my tough tanned shield.' It's repeated over and over throughout, it's how warriors announce their readiness or competence. I find that highly ritualistic as well, not just a drill, but a mental preparation for killing or being killed.
So I don't think its unreasonable in a game of fantasy, in fact I think it's evocative and interesting, to encourage the use of rituals across all the classes.