If, as you speculated, she had "MONEY, and lots of it", especially in 1961, why the heck would anyone want to come to Canada? In 1961, outside of Montreal, Canada was a rural backwater. The health care was far superior in the States back then (and now). Even if she was trying to hide the fact she was unwed, and had money, why wouldn't she simply go to the next U.S. town or county?
The basic fact is that the U.S. is 10 times the size of Canada in population, hence 10 times as wealthy, 10 times the industry, 10 times the hospitals, 10 times the doctors, and [ahem] 10 times the number of unwed mother facilities, with 10 times the people and money to support them, thus 10 times the number of places to hide out, have a kid, and get better care.....if you believe this part of the histoire.
However, none of what you say makes sense to me as a Canadian. Maybe it's because you also have 10 times the number of people who have trouble thinking logically. Personally, I enjoy the intrigue of the "story" that she adopted Obama....which eliminates all the pregnancy issues, the hospital issues, her early recuperation, travel ability, the creation of a revised BC, father ignoring the kid, etc.
Of course, what do I know? After all, there are statistically 1/10th as many smart people up here, than there are down there.
{sigh}
It wouldn't surprise me if we were to learn some day that Stanley Ann was in an unwed mother's home in Canada where her baby was supposed to be put up for adoption, wouldn't surprise me at all, and then in the minutes & hours after giving birth, she decided to NOT let him go, so snatched him from the nursery and got back to the USA where she learned how to correctly diaper her infant son.