by the time I got to the C64 (1988
) everyone had a 1541 disk drive
You were a little late to the party is all. Cassettes were more common in the beginning because the drive cost almost as much as the 64 (which was around $600 in 1982 US dollars). My buddy's older brother bought a C64 summer of 1982. It came with a cassette which I think ran more around $150. One of the games was a pacman type clone that would take 20+ minutes to load. Once you had it running, you didn't turn it off.
Fast-forward to 1984 and I don't know anyone who wasn't buying a 64 without a disk drive. I always believed Commodore made the tapes extra slow on purpose to get you to upgrade to a disk.

Plaz