Mores shame?

Hi everyone,

I've just come across a weird phrase in the iLiKETRAiNS' song "Terra Nova" about Scott's exploration:
"How could I
Have led these men to their demise
And they just follow?
Exploration's last great prize
It wasn't mine

And mores the shame
You will remember my name"

My question is: why "mores the shame" and not "more's tha shame"? What is the meaning of "mores the shame"? I believe it's not about the mere lack of the apostrophe, because the lyrics look like that on all the websites. Also, I found the phrase in other texts, like:

"In 2002 Bartonadle bought out Durmech Eng., who were based in Dudley, the West Midlands and a lot of equipment was transfered down to Hirwaun and I do know that in the late 80,s they had a operate die during a nightshift but do not know the full story.
Maybe worth investigating.
Along with others I worked many nightshift and usually only two of us at a time and never had any experiences, maybe mores the shame by the sounds of it!"
or:
"Unlike the shortlived Circuit des Ardennes Auto Race, the Belgian Grand Prix remains a regular fixture to this day and will have its 66th running in eleven days time. Indeed, the circuit at Spa-Francorchamps has an incredible history that has seen some wonderful racing – mores the shame that the Circuit de Bastogne rings the home of the current Belgian Grand Prix, and no one even knows about it."

Can anyone help?

Marta