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.
I completely agree on this statement. They just don't know how bitcoin works these days, they want to be in in this industry and yet they want to be in. Just do what you need to do. Leave those haters empty handed.