From a legal perspective, PFC is required for loads above 100 W or so, due to limits on harmonic current drawn from the mains grid.
From a technical perspective, power factor correction introduces typically 1 - 10 % loss depending on power level and the technology used, while reducing input current between 25 and 50 %. For higher power loads, this puts much less of a burden on the power network, while introducing manageable losses within the product, so I suspect it would be common even in the absence of legal requirements. PFC stages also usually provide the following stage with a fixed voltage, greatly simplifying their design, and enabling efficient LLC converters to be widely used for fixed output voltage applications, while also allowing universal mains voltage input.
There's also the subject of harmonics. Non-PFC loads with a capacitor input filter draw significant low frequency harmonics, leading to voltage distortion in the mains network. The overall level of harmonic currents in the supply network have to be limited in order to not induce gross mains voltage distortion, which can pose challenges for other loads on the grid.