People are genuinely worried about a Trump govt. Hillary didn't actually support the Hamilton movement, though I do find it funny she lost electors - I think they were mostly just encouraging the GOP electors to defect though.
Had Trump not reached 270, it would have gone to the House. There is a process, and it's not like Trump was actually preferred by a majority of voters anyhow - even as things stand, let alone had people felt there were more viable options.
It would have been rather interesting to see the election fall to the House, and it might have shook things up a bit.