>>34612529>>34612552Injection is for retarded babies with no impulse control (whereas SRing is, of course, for retarded babies with extreme autism). Nothing has any value if you can get whatever you like whenever you'd like it, and injecting ruins the only marginal value shinies have: their rarity.
Think of how unimpressive a shiny Pokémon is -- now think of how utterly unimpressive an injected shiny is. What's the point?