The first is just a frivolous small talk type comment. Non-religious people would say this. It's part of the common US vocabulary. The second is much more serious, and the speaker is actually thanking God for how he is. A non-religious person would never say it.
Religious people do this type of thing all the time in the US. Just look at 1 example- sports. The amount of American pro-athletes who are religious is astounding. Many athletes will seriously thank God after doing something well in a sporting event.
I'm very very anti-theist and I still have a lot of Christians on my Facebook, and some of them are constantly thanking God or praising Jesus for some good thing that happened in their life.
The amount of cars that have religious stickers on them is incredible. Crosses, the Jesus fish, some Biblical reference, a Christian brand, etc- you see them constantly. Maybe it's not like that in the Bay Area, but that is an exception. I live in Germany now and I've counted a total of TWO cars in 2 years that had any kind of Religious sticker.
So, yeah, Christianity is everywhere in the US. I pray for the day that this is not true.