So that the Free Service knows who you are when you come back to use it (the service knows you) also it is used by the service provider to monitor use of the service and perhaps tailor advertising to you.
yes, a playdom account is free.
Yes, a Facebook account is free.
Actually you can have a free VIP account. The way you get this is if someone offers you a account or you get a account from your friends.
Yes, a parent account is free.
My saving account
You can get a free account, registering on the official website (www.runescape.com).
Yes, your Answers account is completely free to use.
There seems to be no way to get a free account.
You can create a free account on roblox at www.roblox.com.
Yes the ABC Family account is free.
yes a club penguin account is free unless you want a membership account
Nope, a YouTube account is free. To create a YouTube account, you need to have a Google account which is also free.