The succinct answer to your question is no, they did not receive free land.
With reference to the family, the proper form of the surname is "Kuhn", and there is no indication that the family were illiterate.
It is important to note that the names of immigrants appear on 3 separate lists, published in Ralph Beaver Strassburger, Pennsylvania German Pioneers, vols. 1-3, Pennsylvania German Society Proceedings, 42 (Norristown, Pennsylvania: Pennsylvania German Society, 1934), commonly known as "Strassburger-Hinke", and accessible online at https://archive.org/details/pennsylvaniagerm03penn_2/page/n5/mode/2up (vol. 1: transcripts of lists), https://archive.org/stream/pennsylvaniagerm43stra#page/n7/mode/2up (vol. 2: facsimiles of ignature lists), and https://archive.org/stream/pennsylvaniagerm44stra#page/n11/mode/2up (vol 3: indexes):
(1) The "Captains' List" (the "A" lists in Strassburger-Hinke), the passenger list proper, compiled by the shipping company. As the shipping companies were English-speaking, the names are spelled phonetically, according to how an 18th-century English-speaker perceived them: the names as spelled can therefore bear little resemblance to their "proper" spelling. The Kuhn family appear on list 29A, pp. 106-107, https://archive.org/details/pennsylvaniagerm03penn_2/page/106/mode/2up .
(2-3) The Oaths of Abjuration and Fidelity (the"B" and "C" lists, respectively, in Strassburger-Hinke). Both lists contain the signatures or marks of the male passengers aged 16 years and older. Abraham and Friedrich Kuhn appear on list 29B, p. 98 (#s 5 and 6 from the top of the page), https://archive.org/stream/pennsylvaniagerm43stra#page/98/mode/2up and on list 29C, p. 101 (#s 5 and 6 from the top of the page), https://archive.org/stream/pennsylvaniagerm43stra#page/100/mode/2up . Friedrich Kuhn signs his name in full on both lists; Abraham Kuhn marks both lists, but the fact he marks with his initials "AK", strongly suggests that he knew how to write, but was unable to sign because of illness that arose during the journey, or because of general disability due to age. On both lists, "Abraham Koen" is written in an English, not a German hand, and is the phonetic spelling of an English-speaking clerk.
As for the origins of the family, the surname Kuhn is common in Southwestern Germany and Alsace, where the majority of 18th century immigrants to Pennsylvania originated. However, whenever possible, immigrants traveled in groups of relatives and neighbors from the same locality. Annette Kunselman Burgert, Eighteenth Century Emigrants from the Northern Alsace to America, Pennsylvania German Society Publications, 26 (Camden, Maine: Picton Press, 1992) has traced several passengers on the Samuel in 1733 to Northern Alsace, including (Hans) Peter Frey (from Wingen = F-67510 Lembach, France; Burgert, p. 174), whose name appears 4 lines above Abraham Kuhn, and Heinrich Bischoff (from Langensoultzbach = F-67360 Woerth, France; Burgert, p. 77), whose name appears 4 lines below Friedrich Kuhn. Burgert (pp. 316-318) gives an account of Christoph Kuhn, age 48, and his son, Adam Simon Kuhn, age 19, who arrived at Philadelphia in 1733, less than 2 weeks after the Samuel, aboard the ship Hope; this Kuhn family appears in the registers of the Lutheran church in F-67690 Hatten, France, but was Reformed (note that "Abraham" is more commonly a Reformed than a Lutheran given name) and was originally from Switzerland.