I don't think anyone has it all figured out. Some are simply more experienced than others. Jane Goodall lived with chimps, is/was an expert on them, and we're still learning things about them. Each level of knowledge simply reveals and provides access to a deeper level of questions.
I wouldn't be so quick to dismiss, though, the possibility that someone can have repeated encounters with bigfoot. If, for example, you live along a migratory route through arid country and right on top of one of the few potable water sources surrounded by better vegetation and an assortment of small prey (essentially an oasis), you're more likely to encounter them on a seasonal basis.
If you camp in dozens of places in the Sierras over the years and find one particularly isolated beautiful spot that you go back to time and again, don't be surprised if they favor it for the same reasons you do (isolation, food sources, water sources, fish, etc), and don't be surprised if they interact with you repeatedly.
But these are happenstance.
Could a person go further and develop an understanding that locations like those above improve his/her chances of encountering and interacting with them? Why not? It is essentially the scientific method. If it pans out there's no reason why that individual shouldn't be able to develop the opportunity to gain more knowledge if they can more regularly put themselves in the same time and space as a group of bigfoot.