from DRBO
[16] And he shall make all, both little and great, rich and poor, freemen and bondmen, to have a character in their right hand, or on their foreheads. [17] And that no man might buy or sell, but he that hath the character, or the name of the beast, or the number of his name. [18] Here is wisdom. He that hath understanding, let him count the number of the beast. For it is the number of a man: and the number of him is six hundred sixty-six.
So the choice would have to be deliberate. The problem is that without the mark no one will be able to buy or sell the necessities of life. I already see protestants saying that they hope to have a friend who will obtain food and water for them, for surely God would not want them or their children to suffer.
It is my opinion, (which is shared by at least three other people that I know of lol) that those with the mark of the beast indeed get their mark deliberately, but in the form of tattoos everywhere, pins, rings and other piercings on their face and other body parts, along with their demonic hair cuts and colorings, and on and on the list can go to include all the different perversions loved by so many people today.
I am not talking about a tattoo or normal earrings or normal hair coloring, I am talking about all those who decorate their bodies to imitate the jungle savages, the savages without God who worship false gods with their body paint, pins, lip and ear saucers, etc,. There are many savage imitators already amongst us. Just go to the grocery store and you're likely to see at least one or two, many more in bigger stores.
As for buying/selling, that is already here as well but only starting, currently, the savages just run you out of restaurants and scream a lot.