And why would you register a domain in a Russian company and not in a Thai company if your service is dedicated to Thai currency?
Maybe because it very cheap to buy in there and easy to make it disappear

but seriously if Op user is from thailand it would better to buy the domain and pay the host server in near Thailand or in the Thailand itself so the latency is minimum
*seems fishy tho
I don't think he can answer that if your service or product is targeting or located in a particular country you have to use the domain extension assign to that country in the case of OP it should be .th, so you're visitors will know who you are servicing and you will be index in the local search engine for that kind of service, you can opt not to use a country domain extension if it has nothing to do with service or product.
I don't think this guy lives or a native of Thailand, he just targeted Thailand visitors.
1. I suppose that it is easy to disappear from any domain provider if you have this goal
2. I like ".com: more than any others but thank's for the idea about local search engine features - I'll use it too.
3. I didn't think about latency and my IT guy didn't informed me about it - general speed of internet is not so high here that's why you will not feel the difference of hosting/server location.