Well, for one thing, Riot themselves said that, if you don't like the thought of players - ally or enemy - utilizing plants, then you should go out of your way to pop them yourself. Plus, the plants themselves are pretty great. Honeyfruit for healing and regaining mana during lulls, Blast Cones for tricky jumps/escapes etc., and Scryer's Bloom for vision. What's not to like?
As for "changing all the jungle camps", they didn't really do too awful much of that. They made the Rift Herald more soloable, they removed the mini-adds on the Red and Blue buffs, they added two more Raptors, made Krugs fall apart, and made the Gromp enrage. So, really, the only camps that got the biggest changes were the buffs, Raptors, and Krugs.
And, lastly, they're treading water they know is likely "dangerous", for lack of better words. They know people - like you - are going to grab their torches, pitchforks and picket signs and start into an uproar about how they don't like change. But, that's the thing: just because you don't like something happening doesn't mean it's going to stop it from happening. Riot is thinking objectively, and further, progressively. They want League of Legends to evolve and become more fun, and in my opinion? They're going the right way about it.