Democracy at work

What is democracy and when does democracy start to be coercive. I'm sure everyone has come across situations where the group decides what each member must do or not do. Everyone must march in lockstep and nobody can march to his/her own drummer. To justify this they use democracy to tell you what you must do (or not do) and god help you if you have a different opinion. You're not a team player, you're not following the party line, you are not right... you are a traitor; you are responsible for breaking up the team. It's all your fault.
No I'm not talking about a strike, nor am I talking about a major negotiation or an election. I'm talking about simple everyday situations that we meet whenever a group gathers. Has majority rule gone too far... I wonder? (I know that it's not politically correct to question this but I've never been PC)
Here's a hypothetical situation to illustrate the point... It is Christmas and in schools there are often Christmas parties at noon with your class. Some teachers don't want to do a party with the kids and that's fine, they are allowed to do what they want during their noon hour, it is their time. So they vote to stop all parties because they don't want any of the kids asking them why they're not doing something. In other words, everyone must do the same thing because they can't assume the consequences of their decision. So instead they bring everyone down to the lowest common denominator. We are not ordering them to do a party on their own time. They are completely free to not do one, yet they use "democracy" to stop others from "doing their thing" because they have trouble taking responsibility for their decisions. Here my illustration uses schools but I am sure that the same situation exists everywhere. (I'm even sure that among the "cols bleus" (municipal workers of Montréal that have a very militant union) there are reasonable workers that just want to get their job done to the best of their abilities and are high jacked by the hotheads of their union.)
It is ironic that in the name of democracy we force a rigid homogenization on people. People should be allowed to be different, to have their own way of doing things, to do things if they want to (or not)... in other words a nice big dose of "live and let live". If not, how do we tell the difference between a tyranny and a democracy?