"Shacking up in a relationship: Are you for or against

I'll start by firmly stating that I am totally against and it has nothing to do with my Christianity, although I can put forward some good points why Christians should not shack up, but as many of the persons who shack- up are not Christians, the discussion is directed towards you.

I grew up in a common-law home (shack up) and majority of the families around me shack-up at some point and I hated it. I vow to myself that while I may have a visiting relationship (at that point I was not a Christian), I would not  shack-up  and even at that point marriage was not high on my list because I did not see much of it growing up.

http://www.interracialdatingcentral.com/fyooz/should-you-really-shack-up/

These are my personal points against  shack-up :

• If you both see each other as good enough to live in a house together why not good enough for marriage. Aren't you already doing every thing set out for married couples?
• Many men are afraid of marriage or that level of commitment. In a shack-up relationship, they get very comfortable. They are getting their sex, their clothes wash, food on the table and the option of leaving you any time they want. Why spoil a 'good' thing? Many women in these relationships wait for years for the man to pop the question, instead they give them several children and then leave and married another woman.
• At some point in  marriage, problems might come up, things might get boring. I believe with marriage persons put extra effort in working hard to maintain the relationship than with shack-up realationships. To me they are quicker to run and again there is nothing holding them to the level of commitment that marriage carries.
• It seems to me with a marriage, men try harder to be committed and most of the times other women seeking out men stand a way off in seeing a married ring, than in a relationship that is seen as merely 'boyfriend and girlfriend'. You ever hear persons say, when they are told to leave people man "but he na marry she (he hasn't married her)"
• I hate to hear big man and women already in their 40s talk about boyfriend and girlfriend and hear joke, they are not married so they cannot say husband/wife, although some, I think realising boyfriend and girlfriend is for young loves, use husband and wife. 
• I cannot understand why some women are in shack-up relationship that are highly abusive and I know a lot about this. Even if you are married, I would not support it even though I understand the legalities there. 
• I hardly ever see the growth in shack-up relationship. What is ours? What have we built together? It seems to me that somehow in shack up relationship, the couple still await marriage secretly before putting things in place for the future. At the end of the day, the woman seems to suffer the most especially when kids are involved and it appears as if the law has nothing in place for common-law relationship just like the way assets are split up for married couples who seek divorce. Maybe a lawyer or some one with that information can help me there.
• I can see what a man get out of shacking up (sex, food and clean clothes and a clean home), but in all my observations, it seems like the woman are always affected negatively. What are they getting? I know most of the time being in love you really don't care, at least at the initial stage, but apart from the kids one after the other, no job in some cases, the $100 that the man sometimes thinks is the world and want you to work miracles to stretch it across the household and he is shock when it finishes, What is gained from shacking up?