Mad because :
1. They can't afford bitcoin.
2. Too late to the trend, they are jelous of peoples who get into the trend long before them so that those peoples earn more than them.
3. They want to make peoples leave bitcoin and chose other digital currency which they have bought with the intention to raise its value, greed are disgusting when are too much that you do anything to get what you want.
4. Etc you can think of.
So don't mind those peoples, only sell your bitcoin or buy it when you see profit.
Exactly. These are people who do not believe in bitcoin when we told them about it. They do not have the guts and braveness we have. They are mad because they really regret the fact that they couod have become rich if they only believe us.