You're confusing two separate issues.

The customer has no care as to how you do the job. The job is worth the same, regardless of whether you work alone, or have help.

The idea of having a helper is for him to... help. A second pair of hands can turn a 3 hr pull into a 15 minute pull. He can make a big difference in set-up and clean-up times. He can greatly reduce the trips up the ladder.