Comment by observationist

Some of the fabs do recycle as effectively as they can, but MRIs use it in a single process, in liquid form, in a relatively constrained container. Fabs use it for a variety of processes, ranging from wafer cooling to purging environments, to making ultra ultra clean chambers. The scale of what they use is higher, too, so even if an individual process is more efficiently recapturing helium, they might go through a few tons a day, with an MRI only using a few liters and losing 5% or less.