You're right that the sources claim that the Helots were treated badly, and they even say that Helots were the worst treated of all slaves in ancient Greece. However, the sources
rarely tell us exactly how the Helots were mistreated. When we do get a glimpse, the only element of the Helots' treatment that stands out is their alleged systematic murder by an established group dedicated solely to that goal -
the Krypteia. Yet, our evidence for the Krypteia is shaky at best, with sources contradicting one another on the purpose of the institution. Moreover, if we compare the Spartans' treatment of the Helots with the Athenians' treatment of their slaves, it appears that, in some ways, the Helots were not really treated as badly as a whole. Indeed, slaves in Athens were regularly beaten, raped (whether by their masters or as unwilling prostitutes), tortured, and killed. On this I would recommend Forsdyke's *Slaves and Slavery in Ancient Greece*, just don't pay attention to what she says about Helots and Cretan slavery, Forsdyke significantly underrepresents contemporary scholarship in that regard.
This is not to say that Helots were well treated, that is hardly the case. Rather, the peculiar system of Spartan citizenship meant that individual masters had to be in Sparta nearly
all the time, and as a result, they could not closely oversee their farms and their Helots in Messenia as their Athenian counterparts could, likely relying on Helot or perioikic overseers to manage farms in their absence. However, for Helots in Laconia, i.e., east of the Taygetos mountains, they were much closer to their masters, and as a result their masters likely exerted greater control over the Helots, with all that entailed.
This is not to say that Helots did not fight back because they were, in some cases, relatively well treated. The conditions that meant that they were relatively autonomous meant that they were also likely to revolt. Such was the case in the mid-fifth century BC, when a group of Helots and *perioikoi*
revolted against Spartan control after an earthquake destroyed much of the city of Sparta. Helots would continue to flee Spartan control throughout much of the Peloponnesian War after the Athenians established two bases from which they encouraged such flight. Unfortunately, we do not know whether individual Helots ever fought back against their masters or the Krypteia outside of the above revolt, we simply do not have the sources necessary for that. Moreover, we do not know what happened in individual cases of the Krypteia's alleged Helot hunting because, as always we do not have the evidence.