Judging by the old newspapers, the kindly people of the North simply couldn’t keep their bond servants from running away. Here are some ads from 1787 issues of the Pennsylvania Gazette:
Ran away last night from the subscriber, living in East Whiteland, Chester county, a SERVANT MAN, named William Thompson, about 5 feet 8 inches high, slim built, of a fair complexion, short fair hair, and sometimes ties it. Took with him a white linen coat, a spotted velvet waistcoat, flowered on the breast and pocket flaps, a pair of white ribbed cotton drawers, a pair of ribbed tow stockings, a pair of charmel pumps almost new, two shirts, two pair of trousers, a German flute, and can play on it well, stamped with the letters J. V. says he was born in England. Whoever takes up the said servant, and secures him in any goal, so that his master may have him again, shall have FOUR DOLLARS reward, and reasonable charges. July 30, 1787. THOMAS HARRIS
EIGHT DOLLARS Reward. Ran away from the subscriber, in New Hanover township, Montgomery county, on the 19th of this instant July, a bound APPRENTICE LAD, named John Rutter, about 19 years of age, blackish hair, a wheelwright by trade; had on and took with him, a flax linnen [sic] shirt and trowsers, wool hat and calf-skin shoes. Whoever takes up the said apprentice, and delivers him to the subscriber, shall have the above reward, and reasonable charges, paid by PHILIP YOST, New Hanover, July 23, 1787
FOUR DOLLARS Reward. Ran away from the subscriber, living in Brandywine hundred, New Cante(? unclear) county, about the 10th instant, an APPRENTICE BOY, named Levi Hughes, about 5 feet 8 inches high, has a down look, fairish hair. Had on when he went away a half worn wool hat, a light coloured cloth jacket without sleeves, tow trowsers, a pair of old shoes, with carved silver buckles, marked A. M. Any person or perons apprehending said apprentice, so that his master may get him again, shall receive the above award, paid by JOS. DAY. July 30, 1787. N. B. The said boy has got a remarkable bad scar on one of his legs.
THREE POUNDS Reward. Ran away from the subscriber on Sunday, the 1st instant, an Irish SERVANT LAD, named Hugh Wilson, about 17 years of age, 5 feet 6 inches high, brown hair, much pitted with the snall pox, had on when he went away, a linen coat and waistcoat, of a copperas colour, tow trousers, an old pair of shoes, and felt hat half worn. Whoever takes up said servant, and secures him so that his master may have him again, shall have the above reward, and all reasonable charges, paid by STEPHEN LOVE. Horsham township, Montgomery county, July 5, 1787.
Philadelphia, July 2, 1787. EIGHT DOLLARS Reward. Ran away from the subscriber, a Dutch SERVANT MAN John Henry Henning, appears to be about 45 years of age, is a middle sized, well set man, professed to be a tallow chandler by trade, understands but little of the English language; having been purchased from on ship board last fall. The fore part of his head is bald, his hair thin, of a light colour, and usually combed back. How he is appareled is uncertain, as he left his usual clothing behind him. Whoever apprehends this [my page ends]
Ran away, the 6th instant August, at night, from the subscriber, living in East Whiteland, Chester county, state of Pennsylvania, a SERVANT MAN, named James Shaerer, about 25 years of age, 5 feet 6 inches high, dark complexion, fresh coloured, short dark brown hair : Had on and took with him a white cloth coat with metal buttons, three jackets cloth and linen, light coloured cloth breeches, several pairs of trowsers, striped and plain, a new wool hat, new shoes and plated buckles. He had been in this country several years past, went to Ireland last fall, and returned again in the ship Friendship, Captain McCadden, who had lately arrived at the port of Philadelphia. Whoever secures said servant, so that his master may have him again, shall be entitled to SIX DOLLARS reward and reasonable charges, paid by THOMAS CUMMINS. August 9, 1787.
On the other hand, an indentured servant (who, compared to the slave, was more of a "rental") would leave at the end of his term, taking with him his "freedom dues" - but if the master worked the indentured servant to death before he served out his term, then he got to keep the servant's freedom bonus.
In the 18th century, it was not unknown for local governments to indenture out impoverished widows and orphans to provide for their support, or for freemen to enter into servitude to work off outstanding debts. Additionally, Great Britain used indentured servitude in the Americas as a way to get rid of the their surplus convict population.
I guess the thing I've gotten most out of studying this subject is the impression that at one time, all over the world, servitude in one form or another was just a form of employment, and had no particular stigma attached to it.
This isn't intended minimize slavery, which was horrendous for the survivors, but rather to point out that servitude (an employment condition where the worker becomes the physical property of the employer) was far more widespread than just the Africans.