I think the reasoning for Wilson being the only one able to make a effigy is that he's the beginning character, therefor he should be the easiest character to play with... Right? I've played Don't Starve quite a bit (my friend is staying over and he has it so he lets me play it) and the longest i've survived is 15 days with Wilson...
For a beginner it's still challenging, and frustrating at times, if you don't have a effigy... and a lot of times I don't survive long enough to make one... So instead of complaining about it, just don't play as Wilson or don't make effigies? You can't expect the devs to limit something that keeps beginners playing because players who actually have experience refuse to play the harder characters.
Anyway, that's my little ramble...