Why fly fast approaches?

I did my BFR last month in a PA28-181. It is an airplane new to the
flying club I belong to and although I have more than 60 hours in type,
the owner requires anyone who desires to rent it, have an instructor
checkout.

Prior to the flight I calculated a weight and balance and appropriate
speeds for the actual takeoff and landing weights.

I started to pull for takeoff at the calculated speed and the
instructor said, "No, no, wait until 65 kts."
Okay.

For the first landing, I stated the calculated 1.5Vso and 1.3Vso speeds.
The instructor again said, "No, no, that's too slow. Use 75 kts."

When we were on the ground, I asked him why he wanted the faster speeds.
His answer was that this was not a new airplane, so the book values
needed to be increased to allow for age related things that could
affect the noted V-speeds.

I can understand the reasoning for a student pilot, the likes of which
this instructor does a lot of training with, but I am 1200+ and over 20
years of flying. I am thinking in terms of performance as would apply
to the Commercial standards. Hence, the reason for calculating the
necessary speeds prior to flight.

I will add that flying at the instructor's recommended speeds leads to
float in the roundout and required more runway. Flying at the
calculated speeds would have resulted in a full stall landing at the
threshhold and clearing at the first turnoff.

What is the perspective of the instructors in this group?
The instructor I fly with knows me. Why would he not hold me to
Commercial standards?