But that too is based on people not knowing the alternatives, as renting managed servers can be close to a wash vs. leasing hardware for a colo (often to the point that relatively cost of land near your preferred managed hosting providers vs. colos that work with access to staff etc. might be what makes one or the other cheaper). Buying outright can be cheaper but isn't necessary.

None of the colo'd setups I've worked on bar one used purchased servers - it's all been leased. But the majority of non-cloud workloads I've worked on have not even been leased, but rented.