Thank you so much

[joyzzz]

I have heard people say Thank you so much in all the places. Even in international Seminars etc, people say this. I want to ask whether this is correct.
Suppose someone says "Thank you so much" and then gestures or indicates the amount by some means then it is ok, but it doesn't happen like that.
If someone says "Thank you so much" to me I would, kind of react by saying "How Much?"
I personally feel that one can say "Thanks a lot", or "Thanks a ton.", or "Thank you very much"
Kindly comment!
I am ancious to see the response from the Experts Gurus of English Language.
Thank you so much.
joyzzz

[Soup]

Thank you so much is a variant of thank you very much, but expresses a more heartfelt, greater thanks.

Travel agent: We were able to get you a flight home for the holidays, and at a reduced rate too.
Sam: Thank you so much. I can't tell you how much I appreciate all the hard work that must have gone into booking me that flight because I know there were no seats available. At least that's what the 4 other travel agent I spoke to told me. Again, thank you so much.

[joyzzz]

Thanks a lot for your explaination, but really i am kind of not too convinced.
Anyway thanks again
God Bless.

[Soup]

Thanks a lot for your explaination, but really i am kind of not too convinced.
Anyway thanks again
God Bless.

Well, y'can't win 'em all.