While it is true that many people are stealing ideas from some other people or some other sites, it is still morally not right IMHO.
I don't think you deserve a negative trust for offering the service though.
I guess my response is that the meaning of 'stealing ideas' changes with different kinds of technology. Is it really stealing to download music, for example? The way websites work, data/designs can be copied so easily that you shouldn't rely solely on your website to offer value to users.
If the only innovative part of a site is the site design itself, it's not really that innovative anyway. PrimeDice isn't hurt by people cloning them, because what they really offer is trust, security, a strong community and the name brand of being the first. reddit is so easy to clone too, but if you clone them you won't get very far because you don't have their established community. What really matters is the underlying value; the website is just what people click on.
Likewise, if I clone a dice game for someone, and he markets it really well and grows a community under him, what he really deserves credit for is growing that community. If
all he does is have me rip off some site and then try to put it out there, no one will play it anyway.
If you invent an iPhone it feels shitty to see Samsung copy it, but software is so malleable that anyone building a website should
expect it to be ripped. You have to offer innovation somewhere else.
Thanks either way though, for keeping an open/tolerant mind and saying that you don't think I deserve negative trust.