You should have specified this then, as a rather large time period as well as geographic space were considered in the OP.I am talking about the millions of daughters of the English peasant/industrial working class.
How would these daughters of agricultural labourers, weavers, spinners, coal miners meet the gentry? How would someone labouring in the fields or labouring as a spinner in an industrial textile mill meet a local lordling?
No, but this is not my point. To clarify, I do not say that such a practice was "common" in all times and places. On the contrary, as far as the general population is concerned, I don't think this had a significant effect. However, one can infer that at certain times and in certain places, such things might have happened more frequently. A study of marriage law in German towns of the 16th century has found that the institution of "secret marriage" was outlawed.Do you have many examples of this?
Why? Looking at the marriage registers, historians found that the children of more well-off households, both female and male, would fall in love (or otherwise bond) with maids and servants sent to work in towns. Generally, until this time, a marriage was consummated the moment one partner agreed to the proposal of the other, and long as both affirmed such a marriage in front of town officials and clerics, it was legally valid and they could not divorce. Now, there might be many forms of secret marriage, one of the more famous ones certainly that of Mary Tudor and the Duke of Suffolk, Charles Brandon.
But, apparently, in the German towns of the 16th century, outlawing that practice might have been a political measure to lower the number of unwanted and unseemly marriages that came with a social (in terms of prestige) and economic (in terms of resources diverted to "unwanted" kids) cost. Assuming this to be true, it is conceivable that for the lesser partner, such a marriage lead to upward social mobility. Had those marriages not had a social effect, i.e. had it been possible to simply get rid of the unwanted partner and possible children so as to avoid integrating them into the wealthier household, there might not have been any reason to make secret marriage illegal. Even more so, towns, in some cases, introduced a "minimum asset" criterion to be eligible for marriage in the first place.