My uncle's old Ford 5000 had a rhythmic knock that sounded like a tired man sighing, and he swore it ran better that way.

Did you try just saying it's not in the budget anymore? I had to be a broken record for a bit, just repeating the same simple "I can't right now" until it stuck.

Exactly, it's a weird social tax on everyone's time. My dentist does the same thing, booking people in overlapping slots. The buffer just becomes part of the mental math for any appointment now.