Townhall Meetings and the Democratic Response

Someone explain this to me. All across the country there have been townhall meetings held by representatives of both houses to explain healthcare reform to their constituents. This is all well and good, but apparently there have been people showing up at these meetings whose only purpose for being there is to disrupt the meeting. They aren't interested in the democratic process or in the need of healthcare for the underserved in our country, but are only interested in ensuring that these meetings are not fruitful.

What I don't understand is why they are allowed. From everything I've seen these people are being brought to these meetings by the busload. Every elected representative in both the House and the Senate have staff working for them. Are these staff members present at these meetings? If not, why not? If they are, are they checking the IDs of the people entering the townhalls to ensure that they live in the area served by that representative? If not, why not?

For the Senate, this only means the person needs to live in the given state, but for the Congress, it's much more restricted. If someone from a different district is doing the demonstrating at the meeting, why are they even there? By denying access to the meeting their freedom of speech is not being denied, as they have the right to speak to their own representative. The constitution does not give freedom of access to meetings.

It seems to me that the Democratic Party is not doing a very good job of addressing this issue, and I'm very disappointed in the party for this. I would hope to see better thinking on the part of the Democrats. We are, after all, the thinking party.