With regard to his economic dealings with them, William Penn showed the Native Americans respect. His descendants were the ones that tipped the wagon (so to speak). There weren't many nice men in history, but William Penn was one of them.
Note that the English Crown set the restrictions on Penn's donation. Penn was not required to buy any land from the local Native Americans.
Most Native Land was acquired or transferred through treaties. The fact that the value of the lands turned out to be substantially higher than what we can now envisage does not imply that the land agreements involved theft or deception.
In the 17th century, William Penn bought a large portion of the Delaware Valley from that country in good faith, but his family did not settle on the majority of the property during his lifetime. When none of the original parties was still alive in 1737, his successors made the decision to learn the full nature of the acquisition. Furthermore, it is obvious that they misinterpreted the agreement's language in order to extract considerably more than the Delaware believed was intended. The Penns employed three runners to make the most of the measurement rather than making a day's journey into the forest to ascertain the amount of land ceded. Little of the tribe's original holdings in the valley was still there. The Walking Purchase was what they termed it.
In order to appease the Native Americans who were not a part of the earlier agreements, the Moravians in Pennsylvania paid for their property numerous times (to various tribes who arrived after the event). However, a large number of the German and Scots-Irish immigrants who came at a later stage in the land purchase process and with little resources migrated through the settled regions to the frontier where they essentially squatted on the property. Two out of every three acres that were occupied on the borderlands were reportedly held without any legal rights other than the modifications that had been done to them.
Many settlers abandoned the practice of surveying their land claims in the middle of the 18th century out of disdain for the schemes of the various land companies, agents, and politicians. Instead, they simply marked boundaries themselves by notching trees or building piles of stones at the corners of boundaries. Whites continued to draw borders for purchases and land grants using Indian pathways and streambeds, which occasionally caused issues in later years when determining the proper bounds of ownership between parties with competing legal interests. This ad hoc system of property division was riddled with errors and contradictory claims, making it difficult and expensive to prove land ownership after the Revolution.