1. That’s the law, and it applies to all visa holders (except LTR). Like in any country, you can try to bend the rules until you get caught.
2. Plenty of people have been fined for this, so don’t listen to those who claim otherwise.
3. It’s a very simple and quick task to complete—no excuse except laziness and disregarding the rules of another country. Definitely not a great start after receiving a cheap and easy five-year visa.
4. Immigration keeps track of these details and may use them against you later.
5. The next time you'll need documents from immigration, get ready to pay for fine.
It's not about being useful to you; it's about being useful for immigration to keep track of you. As a foreigner in Thailand, you must continuously report your updated address. This law applies to all visa holders except those with an LTR visa.