I am wondering why they don't provide a static ip for everybody.
I'm not 100% sure of the interworkings of an ISP, but conceptually, it's easier to have an open pool of IP addresses available than to constantly be updating a list of static IP address for people that are moving locations, upgrading hardware, adding and removing IP addresses to their assigned block, etc. Someone has to pay for that extra management, and for a lot of people, paying the $5-10 a month extra for a feature that has no use to them won't fly well.
If everybody get static ip it would be easier to stop abusers and spammers to enter our site.
Initially, yes it would probably reduce the amount of abuse. But there's always a way around showing your real IP address. It's just a matter of time before everyone knows how to do it anyway.
Proxy should also be banned everywhere.
Proxies have a number of legitimate uses. It's not always a good idea to give away a direct path to your computer. If you were doing something embarrassing but not necessarily illegal and the website you were on got hacked and a list of IPs were published, anyone that knows your IP would see you're on that list.
I have a chat room and it's getting very hard for me to keep abusers and spammers away. When I ban people they reconnect and get a new ip. I can ban their computer but they use private browsing of firefox or some other software.
To stop them I have to ban the complete ip range. I am currently blocking most of the ISP of India and Pakistan and that's all because of a single person.
Relying on an IP for blocking abusive users isn't reliable. If you had a sign-up system with additional filters, you could stop this abuse. Using the Facebook or Google API, you can require your users to have a valid Facebook or Google account before accessing your chat room. These multi-billion dollar companies have excellent technology to prevent abuse of their servers, so you will inherit that. It's not perfect, but it's discouraging to abusers if they have to go through a ton of extra steps just to troll you.
Why don't they provide static ip? Is it stop us from making a server?
Services like DynDNS.org allow you to run a server with a domain name if you have a dynamic IP. You can run servers off of your own IP address anyway, it's just a little harder for people to access your site if your IP is constantly changing.
Maybe with IPv6 a more static system will be created, but the internet is really too complex to be fully static.