If you use the oil-based sealer, how less often would you need to seal it again?
Sometimes, time is money.
OIL seeps in, it doesn't "disappear", but becomes part of the parent material ... wood.
Frequent oilings will tend to saturate the wood requiring less and less oiling.
An artificial sealer , either water based or petroleum (shellac, varnish, polyurethane, Thompson's rip off) , is superficial and disconnected from the wood.
It wears off, flakes off or just evaporates.
Old men want to preserve the wood they have (go ahead ... there ARE jokes in there), and young men are impatient.
Annual oilings that don't need to be "prepared" .. (scraping or other etcetera's) are a pleasant summer task.
Being pissed off because all the money we spent last year looks and acts like shit is un healthful.