Do I recall correctly, that the intake valves are sold (adjustable) tappets, and the exhaust valves have hydraulic (self-adjusting) tappets? If I'm correct about this, it would reflect the nature of intake valves which exhibit relatively little seat wear (cooler and more lubrication from fuel), as opposed to exhaust valves which exhibit relatively more seat wear (hotter, no fuel lubrication).
I would expect very little adjustment would be needed on the intake valves at the 60,000 mile service.