Thor should not have a day dedicated to him. Here are some of the reasons for this:
1) While all the other gods are out battling each other, Thor stays behind and gets hammered on good ole' Nord mead. With his tiny brain and his drunken state of mind, Thor still has the guts to question his father why Loki is next in line for the throne.
2) Whenever Thor visits San Francisco, he always wears an asgard to protect his rear from the natives
3) Whenever he loses his hammer to a thief, Thor always felt the need to dress up as a prostitute to persuade the thief to give back his hammer.
Essentially, Thor is a drunken homophobic hypocrite who wimped out on battles.
The worst part is that we have a day dedicated to him.