How Can You Be "More Than Welcome" ?!

This phrase, along with others like "more than happy" ... just doesn't make sense.

To be "more than" suggests you begin at a certain place and then proceed further or increase from that starting point.  There is an initial frame of reference and the more than explains the addition or expansion.  This works when you're talking about something like a slice of pie ("Can I get more than she has?") or maybe money ("This should be more than enough to cover the cost.") ... But when you are talking about abstract points of reference, such as "happy" or "welcome" it is just impossible to really apply the more than moniker.

What is more than happy?  Are there units of happiness and "happy" isn't at the top of this chart?

What is more than welcome?  Is there a welcome range where "You're Welcome" is somewhere near the middle of welcomeness?

Just say it so it makes sense.  Please.

Song Of The Day:
I love the country group Little Big Town, but their song "A Little More You" fits in with my question related to this blog post.  How does a person give a little more of themselves?  According to the music video, it seems like they are referring to less clothing ... but that can't be it can it?

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