I think there are evolutionary arguments for it, besides avoiding sickness: * Generally, the opposite sex is physically attracted to fit individuals. * Findin

I think there are evolutionary arguments for it, besides avoiding sickness: * Generally, the opposite sex is physically attracted to fit individuals. * Finding food prior to agriculture or paying others. * As for sugar, I'm not so sure, but maybe the plant's benefits also have to be considered (e.g. propagating seeds through fruits).